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$750,000,000

Common Shares, Preferred Shares, Depositary Shares,

18,460,000 Common Shares of Platinum Underwriters Holdings, Ltd. Offered by Selling Shareholders

        We may offer and sell from time to time:

      In addition, selling shareholders named in this prospectus may sell up to 18,460,000 of our common shares, which includes 8,500,000 common shares issuable upon exercise of outstanding options. We will not receive any of the proceeds from the sale of our common shares by selling shareholders.

      We will provide the specific terms and initial public offering prices of these securities in supplements to this prospectus. You should read this prospectus and any supplement carefully before you invest.

       Investing in these securities involves certain risks. See “Risk Factors” on page 1.

       These securities may be sold to or through underwriters and also to other purchasers or through agents. The names of any underwriters or agents and the specific terms of a plan of distribution will be stated in an accompanying prospectus supplement.

      These securities may be sold in one or more offerings up to a total dollar amount of $750,000,000.

      Our common shares are traded on the New York Stock Exchange under the symbol “PTP.” Other than for our common shares, there is no market for the other securities we may offer.

      None of the Securities and Exchange Commission, any state securities commission, the registrar of companies in Bermuda or the Bermuda Monetary Authority has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

      This prospectus may not be used to consummate sales of offered securities unless accompanied by a prospectus supplement.

The date of this prospectus is June 28, 2004.

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IMPORTANT INFORMATION ABOUT THIS PROSPECTUS

      You should rely only on the information contained in this document or to which we have referred you. We have not authorized anyone to provide you with information that is different. This document may only be used where it is legal to sell these securities. The information in this document may only be accurate on the date of this document.

      Consent under the Exchange Control Act 1972 (and its related regulations) has been obtained from the Bermuda Monetary Authority for the issue and transfer of our offered securities to and between non-residents of Bermuda for exchange control purposes provided our common shares remain listed on an appointed stock exchange, which includes the New York Stock Exchange. The issue and transfer of in excess of 20% of our shares involving any persons regarded as resident in Bermuda for exchange control purposes requires prior authorization from the Bermuda Monetary Authority. This prospectus will be filed with the Registrar of Companies in Bermuda in accordance with Bermuda law. In granting such consent and in accepting this prospectus for filing, neither the Bermuda Monetary Authority nor the Registrar of Companies in Bermuda accepts any responsibility for our financial soundness or the correctness of any of the statements made or opinions expressed in this prospectus.

      References in this prospectus to “dollars” or “$” are to the lawful currency of the United States of America, unless the context otherwise requires.

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AVAILABLE INFORMATION

      This prospectus is part of a registration statement that we have filed with the Securities and Exchange Commission using a “shelf” registration process, relating to the common shares, preferred shares, depositary shares, debt securities, warrants, purchase contracts, purchase units, preferred securities and preferred securities guarantees described in this prospectus. This means:

      This prospectus provides you with a general description of the securities we or any selling shareholder may offer. This prospectus does not contain all of the information set forth in the registration statement as permitted by the rules and regulations of the Commission. For additional information regarding us and the offered securities, please refer to the registration statement. Each time we or any selling shareholder sell securities, we or any selling shareholder will provide a prospectus supplement that will contain specific information about the terms of that offering. The prospectus supplement may also add, update or change information contained in this prospectus. You should read both this prospectus and any prospectus supplement together with additional information described under the heading “Where You Can Find More Information.” In this prospectus, references to the “Company,” “Platinum,” “we,” “us” and “our” refer to Platinum Underwriters Holdings, Ltd.’s consolidated operations unless the context otherwise indicates. “Platinum Holdings” refers solely to Platinum Underwriters Holdings, Ltd. “Platinum US” refers to Platinum Underwriters Reinsurance, Inc. “Platinum UK” refers to Platinum Re (UK) Limited. “Platinum Bermuda” refers to Platinum Underwriters Bermuda, Ltd. “Platinum Ireland” refers to Platinum Regency Holdings. “Platinum Finance” refers to Platinum Underwriters Finance, Inc.

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PLATINUM UNDERWRITERS HOLDINGS, LTD.

      Platinum Holdings is a leading provider of property, casualty, and finite reinsurance coverages, through reinsurance intermediaries, to a diverse clientele on a worldwide basis. Platinum operates through its principal subsidiaries in Bermuda, the United States and the United Kingdom.

      Our principal executive offices are located at The Belvedere Building, 69 Pitts Bay Road, Pembroke, Bermuda HM 08. Our telephone number is (441) 295-7195.

      For further information regarding Platinum, including financial information, you should refer to our recent filings with the Securities and Exchange Commission.

RISK FACTORS

      Investing in our securities involves risk. Please see the risk factors described in our Annual Report on Form 10-K for our most recent fiscal year, which are incorporated by reference in this prospectus. Before making an investment decision, you should carefully consider these risks as well as other information we include or incorporate by reference in this prospectus. The risks and uncertainties we have described are not the only ones facing our company. Additional risks and uncertainties not presently known to us or that we currently deem immaterial may also affect our business operations. Additional risk factors may be included in a prospectus supplement relating to a particular series or offering of securities.

GENERAL DESCRIPTION OF THE OFFERED SECURITIES

      We may from time to time offer under this prospectus, separately or together:

      The selling shareholders may offer up to 18,460,000 of our common shares, which includes 8,500,000 common shares issuable upon exercise of outstanding options.

      The aggregate initial offering price of these offered securities will not exceed $750,000,000.

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RATIO OF EARNINGS TO FIXED CHARGES

      The following table sets forth our earnings to fixed charges for the periods ended December 31, 2003 and 2002:

      For purposes of computing these ratios, earnings consist of net income. Fixed charges consist of interest expense and amortization of capitalized debt expenses.

FORWARD-LOOKING STATEMENTS

      This prospectus and the documents incorporated by reference into this prospectus contain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934 (the “Exchange Act”). Forward-looking statements are necessarily based on estimates and assumptions that are inherently subject to significant business, economic and competitive uncertainties and contingencies, many of which, with respect to future business decisions, are subject to change. These uncertainties and contingencies can affect actual results and could cause actual results to differ materially from those expressed in any forward-looking statements made by, or on behalf of, us.

      In particular, statements using words such as “may,” “should,” “estimate,” “expect,” “anticipate,” “intend,” “believe,” “predict,” “potential,” or words of similar import generally involve forward-looking statements. This prospectus and the documents incorporated by reference into this prospectus also contain forward-looking statements with respect to our business and industry, such as those relating to our strategy and management objectives and trends in market conditions, market standing, product volumes, investment results and pricing conditions.

      In light of the risks and uncertainties inherent in all future projections, the inclusion of forward-looking statements in this prospectus should not be considered as a representation by us or any other person that our objectives or plans will be achieved. Numerous factors could cause our actual results to differ materially from those in the forward-looking statements, including the following:

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      As a consequence, current plans, anticipated actions and future financial condition and results may differ from those expressed in any forward-looking statements made by or on behalf of the Company. The foregoing factors, should not be construed as exhaustive. Additionally, forward-looking statements speak only as of the date they are made, and we undertake no obligation to release publicly the results of any future revisions or updates we may make to forward-looking statements to reflect new information or circumstances after the date hereof or to reflect the occurrence of future events.

USE OF PROCEEDS

      Unless indicated otherwise in a prospectus supplement, we expect to use the net proceeds from the sale of the securities for general corporate purposes, including working capital, capital expenditures, share repurchase programs and acquisitions.

      We will not receive any proceeds from the sale of our common shares by any Selling Shareholder in such an offering.

DESCRIPTION OF OUR SHARE CAPITAL

      The following description of the share capital of Platinum Holdings summarizes certain provisions of Platinum Holdings’ Bye-laws, and is qualified in its entirety by reference to such Bye-laws. A copy of Platinum Holdings’ Bye-laws is filed as an exhibit to the registration statement of which this prospectus is a part.

General

      As of March 12, 2004, Platinum Holdings’ authorized share capital consisted of: (i) 200,000,000 common shares, par value $0.01 per share, of which 43,265,525 common shares were outstanding and (ii) 25,000,000 preferred shares, par value $0.01 per share, none of which were outstanding. As of March 1, 2004 there were approximately 16 holders of record of our common shares, including The St. Paul Travelers Companies, Inc., (formerly The St. Paul Companies, Inc.) (“St. Paul”), which held 6,000,000 common shares (the voting power of which is limited to 9.9% as described below) and an option to acquire 6,000,000 common shares, and RenaissanceRe Holdings Ltd. (“RenaissanceRe”), which held 3,960,000 common shares (the voting power of which is limited to 9.9% as described below) and an option to acquire 2,500,000 common shares.

Common Shares

      Holders of common shares have no pre-emptive, redemption, conversion or sinking fund rights, provided, however, that pursuant to a Formation and Separation Agreement dated as of October 28, 2002 between the Company and St. Paul (the “Formation Agreement”) and a Transfer Restrictions, Registration Rights and Standstill Agreement between the Company and RenaissanceRe dated as of November 1, 2002, Platinum Holdings has granted St. Paul and RenaissanceRe respectively, the pre-emptive rights specified therein. See “Related Party Transactions.” Subject to the limitation on voting rights described below, holders of common shares are entitled to one vote per share on all matters submitted to a vote of holders of common shares. Most matters to be approved by holders of common shares require approval by a simple majority vote. The holders of at least 75% of the common shares voting in person or by proxy at a meeting must approve an amalgamation

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      In the event of a liquidation, winding-up or dissolution of Platinum Holdings, whether voluntary or involuntary or for the purpose of a reorganization or otherwise or upon any distribution of capital, the holders of common shares are entitled to share equally and ratably in the assets of Platinum Holdings, if any, remaining after the payment of all of its debts and liabilities and the liquidation preference of any outstanding preferred shares. All outstanding common shares are fully paid and nonassessable. Authorized but unissued shares may, subject to any rights attaching to any existing class or classes of shares, be issued at any time and at the discretion of the Board of Directors without the approval of the shareholders of the Company with such rights, preferences and limitations as the Board may determine.

Limitation on Voting Rights

      Each common share has one vote on a poll of the shareholders, except that, if and for as long as the number of issued Controlled Shares (as defined below) of any person would constitute 10% or more of the combined voting power of the issued common shares of Platinum Holdings (after giving effect to any prior reduction in voting power as described below), each issued Controlled Share, regardless of the identity of the registered holder thereof, will confer a fraction of a vote as determined by the following formula:

(T - C)/ (9.1 × C)

      The formula will be applied successively as many times as may be necessary to ensure that no person will be a 10% Shareholder (as defined below) at any time (the “sequencing provision”). For the purposes of determining the votes exercisable by shareholders as of any date, the formula first will be applied to the common shares of each shareholder in declining order based on the respective numbers of total Controlled Shares attributable to each shareholder. Thus, the formula will be applied first to the votes of common shares held by the shareholder to whom the largest number of total Controlled Shares is attributable and thereafter sequentially with respect to the shareholder with the next largest number of total Controlled Shares. The formula will be applied iteratively thereafter to ensure that no person will be a 10% Shareholder. In each case, calculations are made on the basis of the aggregate number of votes conferred by the issued common shares as of such date, as reduced by the application of the formula to any issued common shares of any shareholder with a larger number of total Controlled Shares as of such date. A “10% Shareholder” means a person who owns, in the aggregate, (i) directly, (ii) with respect to persons who are U.S. persons, by application of the attribution and constructive ownership rules of Sections 958(a) and 958(b) of the Code or (iii) beneficially,

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      Because of the voting limitation described in the preceding paragraph, the common shares owned by St. Paul and RenaissanceRe have reduced voting rights. Should St. Paul or RenaissanceRe dispose of some or all of the common shares it owns, the reduced voting rights with respect to the common shares disposed of by St. Paul or RenaissanceRe will be eliminated (except if the disposition is to any other person who holds, or who as a result of such transaction would hold, 10% or more of our total voting rights), and those common shares thereafter will be entitled to full voting rights, subject to future dilution to avoid creating a 10% Shareholder. Therefore, the voting power of the common shares held by all of our shareholders other than St. Paul or RenaissanceRe will be diluted upon any such disposition by St. Paul or RenaissanceRe.

      Our directors are empowered to require any shareholder to provide information as to that shareholder’s beneficial ownership of common shares, the names of persons having beneficial ownership of the shareholder’s common shares, relationships, associations or affiliations with other shareholders or any other facts the directors may deem relevant to a determination of the number of Controlled Shares attributable to any person. Our directors may disregard the votes attached to the common shares of any holder failing to respond to such a request or submitting incomplete or untrue information.

      Our directors retain certain discretion to make such final adjustments to the aggregate number of votes attaching to the common shares of any shareholder that they consider fair and reasonable in all the circumstances to ensure that no person will be a 10% Shareholder at any time.

Restrictions on Transfer

      Our Bye-laws contain several provisions restricting the transferability of common shares. The directors are required to decline to register a transfer of common shares if they have reason to believe that the result of such transfer would be (i) that any person other than a St. Paul Person or a RenaissanceRe Person (as defined below) would become or continue to be a 10% Shareholder or (ii) that a St. Paul Person or a RenaissanceRe Person would become or continue to be a United States 25% Shareholder (as defined below), in each case without giving effect to the limitation on voting rights described above. Similar restrictions apply to Platinum Holdings’ ability to issue or repurchase common shares. “St. Paul Person” means any of St. Paul and its affiliates and a “RenaissanceRe Person” means any of RenaissanceRe and its affiliates. A “United States 25% Shareholder” means a U.S. person who owns, directly or by application of the constructive ownership rules of Sections 958(a) and 958(b) of the Code, 25% or more of either (i) the total combined voting rights attaching to the issued common shares and the issued shares of any other class of Platinum Holdings or (ii) the total combined value of the issued common shares and any other issued shares of Platinum Holdings, determined pursuant to Section 957 of the Code. Only for the purposes of these provisions of our Bye-laws, it is assumed that all RenaissanceRe Persons are U.S. Persons. These restrictions on the transfer, issuance or repurchase of shares do not apply to any issuance of common shares pursuant to a contract to purchase common shares from Platinum Holdings included in the 7.00% equity security units issued by Platinum Holdings, though the limitations on voting rights, discussed above, do apply to such common shares.

      Our directors also may, in their absolute discretion, decline to register the transfer of any common shares if they have reason to believe (i) that the transfer may expose us, any of our subsidiaries, any shareholder or any person ceding insurance to any of our subsidiaries to adverse tax or regulatory treatment in any jurisdiction or (ii) that registration of the transfer under the Securities Act of 1933, as amended (“Securities Act”) or under any U.S. state securities laws or under the laws of any other jurisdiction is required and such registration has not been duly effected. In addition, our directors may decline to approve or register a transfer of common shares unless all applicable consents, authorizations, permissions or approvals of any governmental body or agency in Bermuda, the United States or any other applicable jurisdiction required to be obtained prior to such transfer shall have been obtained.

      We are authorized to request information from any holder or prospective acquiror of common shares as necessary to give effect to the transfer, issuance and repurchase restrictions described above, and may decline to effect any transaction if complete and accurate information is not received as requested.

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      Conyers, Dill & Pearman, our Bermuda counsel, has advised us that while the precise form of the restrictions on transfer contained in our Bye-laws is untested, as a matter of general principle, restrictions on transfers are enforceable under Bermuda law and are not uncommon. A proposed transferee will be permitted to dispose of any common shares purchased that violate the restrictions and as to the transfer of which registration is refused. The proposed transferor of those common shares will be deemed to own those common shares for dividend, voting and reporting purposes until a transfer of such common shares has been registered on the register of shareholders of Platinum Holdings.

      If the directors refuse to register a transfer for any reason, they must notify the proposed transferor and transferee within thirty days of such refusal. Our Bye-laws also provide that our Board of Directors may suspend the registration of transfers for any reason and for such periods as it may determine, provided that it may not suspend the registration of transfers for more than 45 days in any period of 365 consecutive days.

      Our directors may designate our Chief Executive Officer to exercise their authority to decline to register transfers or to limit voting rights as described above, or to take any other action, for as long as the Chief Executive Officer is also a director.

      The voting restrictions and restrictions on transfer described above may have the effect of delaying, deferring or preventing a change in control of Platinum Holdings.

Preferred Shares

      Pursuant to our Bye-laws and Bermuda law, our Board of Directors by resolution may establish one or more series of preferred shares having a number of shares, designations, relative voting rights, dividend rates, liquidation and other rights, preferences, limitations and powers as may be fixed by the Board of Directors without any further shareholder approval which, if any preferred shares are issued, will include restrictions on voting and transfer intended to avoid having us become a “controlled foreign corporation” for U.S. federal income tax purposes. If our Board of Directors issues preferred shares conferring any voting rights, it will amend our Bye-laws to apply the limitations on the voting rights discussed above under “— Limitation on Voting Rights” to those preferred shares. Any rights, preferences, powers and limitations as may be established could also have the effect of discouraging an attempt to obtain control of the Company. The issuance of preferred shares could also adversely affect the voting power of the holders of our common shares, deny such holders the receipt of a premium on their common shares in the event of a tender or other offer for the common shares and depress the market price of the common shares.

Bye-Laws

      Our Bye-laws provide for our corporate governance, including the establishment of share rights, modification of those rights, issuance of share certificates, imposition of a lien over shares in respect of unpaid amounts on those shares, calls on shares which are not fully paid, forfeiture of shares, the transfer of shares, alterations of capital, the calling and conduct of general meetings of shareholders, proxies, the appointment and removal of directors, conduct and power of directors, the payment of dividends, the appointment of an auditor and our winding-up.

      Our Bye-laws provide that our Board of Directors shall be elected annually and shall not be staggered. Shareholders may only remove a director for cause prior to the expiration of that director’s term at a special meeting of shareholders at which a majority of the holders of shares voting thereon vote in favor of that action.

      Our Bye-laws also provide that if our Board of Directors in its absolute discretion determines that share ownership by any shareholder may result in adverse tax, regulatory or legal consequences to us, any of our subsidiaries or any other shareholder, then we will have the option, but not the obligation, to repurchase all or part of the shares held by such shareholder to the extent the Board of Directors determines it is necessary to avoid such adverse or potential adverse consequences. The price to be paid for such shares will be the fair market value of such shares.

      Our Bye-laws provide that when any matter is required to be submitted to a vote of the shareholders of any direct or indirect non-U.S. subsidiary of the Company, the Company is required to submit a proposal

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      Our shareholders will consider and vote upon a proposal to remove this provision from our Bye-laws at our annual general meeting of shareholders to be held on May 6, 2004.

Transfer Agent

      Our registrar and transfer agent for the common shares is Mellon Investor Services LLC.

Differences in Corporate Law

      The Companies Act differs in certain material respects from laws generally applicable to U.S. corporations and their shareholders. Set forth below is a summary of certain significant provisions of the Companies Act (including modifications adopted pursuant to our Bye-laws) applicable to us, which differ in certain respects from provisions of Delaware corporate law, which is the law that governs many U.S. public companies. The following statements are summaries, and do not purport to deal with all aspects of Bermuda law that may be relevant to us and our shareholders.

      Interested Directors. Our Bye-laws provide that transactions we enter into in which a director has an interest are not voidable by us, nor can the interested director be liable to us for any profit realized pursuant to such transactions, provided the nature of the interest is disclosed at the first opportunity at a meeting of directors, or in writing to the directors. Under Delaware law, such a transaction would not be voidable if (i) the material facts as to the interested director’s relationship or interests are disclosed or are known to the board of directors and the board in good faith authorized the transaction by the affirmative vote of a majority of the disinterested directors, even though the disinterested directors constitute less than a quorum, (ii) the material facts as to the director’s relationship or interest and as to the transaction are disclosed or are known to the shareholders entitled to vote on the transaction and the transaction is specifically approved in good faith by vote of the shareholders or (iii) the transaction is fair to the corporation as of the time it is authorized, approved or ratified by the board of directors, a committee of the board of directors or the shareholders. Under Delaware law, the interested director could be held liable for a transaction in which that director derived an improper personal benefit.

      Mergers and Similar Arrangements. We may acquire the business of another Bermuda company or a company incorporated outside Bermuda and carry on such business when it is within the objects of our memorandum of association. In the case of an amalgamation, we may amalgamate with another Bermuda company or with an entity incorporated outside Bermuda. A shareholder who did not vote in favor of the amalgamation may apply to a Bermuda court for a proper valuation of his or her shares if he or she is not satisfied that fair value has been offered for those shares. The court ordinarily would not disapprove the transaction on that ground absent evidence of fraud or bad faith. Under Delaware law, with certain exceptions, a merger, consolidation or sale of all or substantially all the assets of a corporation must be approved by the board of directors and the holders of a majority of the outstanding shares entitled to vote thereon. Under Delaware law, a stockholder of a corporation participating in certain major corporate transactions may, under certain circumstances, be entitled to appraisal rights pursuant to which the stockholder may receive cash in the amount of the fair value of the shares held by that stockholder (as determined by a court) in lieu of the consideration that stockholder would otherwise receive in the transaction. Delaware law does not provide stockholders of a corporation with voting or appraisal rights when the corporation acquires another business through the issuance of its stock or other consideration (i) in exchange for the assets of the business to be acquired, (ii) in exchange for the outstanding stock of the corporation to be acquired; (iii) in a merger of the corporation to be acquired with a subsidiary of the acquiring corporation or (iv) in a merger in which the corporation’s certificate of incorporation is not amended and the corporation issues less than 20% of its common stock outstanding prior to the merger.

      Takeovers. Bermuda law provides that where an offer is made for shares of another company and, within four months of the offer, the holders of not less than 90% of the shares which are the subject of the offer

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      Shareholder’s Suit. The rights of shareholders under Bermuda law are not as extensive as the rights of shareholders under legislation or judicial precedent in many U.S. jurisdictions. Class actions and derivative actions are generally not available to shareholders under the laws of Bermuda. However, the Bermuda courts ordinarily would be expected to follow English case law precedent, which would permit a shareholder to commence an action in our name to remedy a wrong done to us where the act complained of is alleged to be beyond our corporate power or is illegal or would result in the violation of our memorandum of association or Bye-laws. Furthermore, consideration would be given by the court to acts that are alleged to constitute a fraud against the minority shareholders or where an act requires the approval of a greater percentage of shareholders than actually approved it. The winning party in such an action generally would be able to recover a portion of attorneys’ fees incurred in connection with such action. Class actions and derivative actions generally are available to stockholders under Delaware law for, among other things, breach of fiduciary duty, corporate waste and actions not taken in accordance with applicable law. In such actions, the court has discretion to permit the winning party to recover attorneys’ fees incurred in connection with such action.

      Indemnification of Directors. Our Bye-laws indemnify our directors and officers in their capacity as such in respect of any loss arising or liability attaching to them by virtue of any rule of law in respect of any negligence, default, breach of duty or breach of trust of which a director or officer may be guilty in relation to us other than in respect of his own fraud or dishonesty, which is the maximum extent of indemnification permitted under the Companies Act. Under Delaware law, a corporation may indemnify a director or officer of the corporation against expenses (including attorneys’ fees), judgments, fines and amounts paid in settlement actually and reasonably incurred in defense of an action, suit or proceeding by reason of such position if (i) the director or officer acted in good faith and in a manner he reasonably believed to be in or not opposed to the best interests of the corporation and (ii) with respect to any criminal action or proceeding, if the director or officer had no reasonable cause to believe his conduct was unlawful.

      Inspection of Corporate Records. Members of the general public have the right to inspect our public documents available at the office of the Registrar of Companies in Bermuda, which will include our memorandum of association (including our objects and powers) and alterations to our memorandum of association, including any increase or reduction of our authorized capital. Our shareholders have the additional right to inspect our Bye-laws, minutes of general meetings and our audited financial statements, which must be presented to the annual general meeting of shareholders. Our register of shareholders is also open to inspection by shareholders without charge, and to members of the public for a fee. We are required to maintain a share register in Bermuda but may establish a branch register outside Bermuda. We are required to keep at our registered office a register of our directors and officers which is open for inspection by members of the public without charge. Bermuda law does not, however, provide a general right for shareholders to inspect or obtain copies of any other corporate records. Delaware law permits any stockholder to inspect or obtain copies of a corporation’s stockholder list and its other books and records for any purpose reasonably related to such person’s interest as a stockholder.

      Enforcement of Judgments and Other Matters. We have been advised by Conyers, Dill & Pearman, our Bermuda counsel, that there is doubt as to whether the courts of Bermuda would enforce (1) judgments of United States courts obtained in actions against us or our directors and officers, as well as the experts named in this prospectus who reside outside the United States predicated upon the civil liability provisions of the United States federal securities laws and (2) original actions brought in Bermuda against us or our directors and officers, as well as the experts named in this prospectus who reside outside the United States predicated solely

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DESCRIPTION OF THE DEPOSITARY SHARES

General

      We may, at our option, elect to offer depositary shares, each representing a fraction (to be set forth in the prospectus supplement relating to our common shares or a particular series of preferred shares) of a common share or a fraction of a share of a particular class or series of preferred shares as described below. In the event we elect to do so, depositary receipts evidencing depositary shares will be issued to the public.

      The common shares or the shares of the class or series of preferred shares represented by depositary shares will be deposited under a deposit agreement among us, a depositary selected by us and the holders of the depositary receipts. The depositary will be a bank or trust company having its principal office in the United States and having a combined capital and surplus of at least $50,000,000. Subject to the terms of the deposit agreement, each owner of a depositary share will be entitled, in proportion to the applicable fraction of a common share or preference share represented by such depositary share, to all the rights and preferences of the common shares or preferred shares represented thereby (including dividend, voting, redemption and liquidation rights). The depositary shares will be evidenced by depositary receipts issued pursuant to the deposit agreement. Depositary receipts will be distributed to those persons purchasing the fractional common shares or fractional shares of the applicable class or series of preferred shares in accordance with the terms of the offering described in the related prospectus supplement. Forms of the deposit agreement and depositary receipt have been filed as exhibits to the registration statement of which this prospectus forms a part.

      Pending the preparation of definitive depositary receipts, the depositary may, upon our written order, issue temporary depositary receipts substantially identical to (and entitling the holders thereof to all the rights pertaining to) the definitive depositary receipts but not in definitive form. Definitive depositary receipts will be prepared thereafter without unreasonable delay, and temporary depositary receipts will be exchangeable for definitive depositary receipts without charge to the holder thereof.

      The following description of the depositary shares sets forth the material terms and provisions of the depositary shares to which any prospectus supplement may relate. The particular terms of the depositary shares offered by any prospectus supplement, and the extent to which the general provisions described below may apply to the offered securities, will be described in the prospectus supplement, which will also include a discussion of certain U.S. federal income tax considerations.

Dividends and Other Distributions

      The depositary will distribute all cash dividends or other distributions received in respect of the related common shares or preferred shares to the record holders of depositary shares relating to such common shares or preferred shares in proportion to the number of such depositary shares owned by such holders.

      In the event of a distribution other than in cash, the depositary will distribute property received by it to the record holders of depositary shares entitled thereto, unless the depositary determines that it is not feasible to make such distribution, in which case the depositary may, with our approval, sell such property and distribute the net proceeds from the sale to such holders.

Withdrawal of Shares

      Upon surrender of the depositary receipts at the corporate trust office of the depositary (unless the related depositary shares have previously been called for redemption), the holder of the depositary shares evidenced thereby is entitled to delivery of the number of whole shares of the related common shares or class or series of

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Redemption of Depositary Shares

      Whenever we redeem common shares or preferred shares held by the depositary, the depositary will redeem as of the same redemption date the number of depositary shares representing common shares or shares of the related class or series of preferred shares so redeemed. The redemption price per depositary share will be equal to the applicable fraction of the redemption price per share payable with respect to such common shares or class or series of preferred shares. If less than all the depositary shares are to be redeemed, the depositary shares to be redeemed will be selected by lot or pro rata as may be determined by the depositary.

Voting the Common Shares or Preferred Shares

      Upon receipt of notice of any meeting at which the holders of common shares or preferred shares are entitled to vote, the depositary will mail the information contained in such notice of meeting to the record holders of the depositary shares relating to such common shares or preferred shares. Each record holder of such depositary shares on the record date (which will be the same date as the record date for common shares or preferred shares, as applicable) will be entitled to instruct the depositary as to the exercise of the voting rights pertaining to the amount of common shares or preferred shares represented by such holder’s depositary shares. The depositary will endeavor, insofar as practicable, to vote the number of the common shares or preferred shares represented by such depositary shares in accordance with such instructions, and we will agree to take all action which the depositary deems necessary in order to enable the depositary to do so. The depositary will vote all common shares or preferred shares held by it proportionately with instructions received if it does not receive specific instructions from the holders of depositary shares representing such common shares or preferred shares.

Amendment and Termination of the Deposit Agreement

      The form of depositary receipt evidencing the depositary shares and any provision of the deposit agreement may at any time be amended by agreement between us and the depositary. However, any amendment which materially and adversely alters the rights of the holders of depositary receipts will not be effective unless such amendment has been approved by the holders of depositary receipts representing at least a majority (or, in the case of amendments relating to or affecting rights to receive dividends or distributions or voting or redemption rights, 66%, unless otherwise provided in the related prospectus supplement) of the depositary shares then outstanding. The deposit agreement may be terminated by us or the depositary only if (1) all outstanding depositary shares have been redeemed, (2) there has been a final distribution in respect of the common shares or the preferred shares in connection with our liquidation, dissolution or winding up and such distribution has been distributed to the holders of depositary receipts or (3) upon the consent of holders of depositary receipts representing not less than 66% of the depositary shares outstanding, unless otherwise provided in the related prospectus supplement.

Charges of Depositary

      We will pay all transfer and other taxes and governmental charges arising solely from the existence of the depositary arrangements. We will also pay charges of the depositary in connection with the initial deposit of the related common shares or preferred shares and any redemption of such common shares or preferred

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      The depositary may refuse to effect any transfer of a depositary receipt or any withdrawal of common shares or preferred shares evidenced thereby until all such taxes and charges with respect to such depositary receipt or such common shares or preferred shares are paid by the holders thereof.

Miscellaneous

      The depositary will forward all reports and communications from us which are delivered to the depositary and which we are required to furnish to the holders of common shares or preferred shares.

      Neither we nor the depositary will be liable if either of us is prevented or delayed by law or any circumstance beyond our control in performing our obligations under the deposit agreement. Our obligations and the obligations of the depositary under the deposit agreement will be limited to performance in good faith of their duties thereunder and neither we nor the depositary will be obligated to prosecute or defend any legal proceeding in respect of any depositary shares or class or series of preferred shares unless satisfactory indemnity is furnished. We and the depositary may rely on written advice of counsel or accountants, or information provided by persons presenting preferred shares for deposit, holders of depositary shares or other persons believed to be competent and on documents believed to be genuine.

Resignation and Removal of Depositary

      The depositary may resign at any time by delivering to us notice of its election to do so, and we may at any time remove the depositary. Any such resignation or removal of the depositary will take effect upon the appointment of a successor depositary, which successor depositary must be appointed within 60 days after delivery of the notice of resignation or removal and must be a bank or trust company having its principal office in the United States and having a combined capital and surplus of at least $50,000,000.

DESCRIPTION OF THE DEBT SECURITIES

General

      The following description of our debt securities sets forth the material terms and provisions of the debt securities to which any prospectus supplement may relate and may be amended or supplemented by terms described in the applicable prospectus supplement. Our senior debt securities are to be issued under a senior indenture between us and JPMorgan Chase Bank, as trustee, as supplemented. Our subordinated debt securities are to be issued under a subordinated indenture between us and JPMorgan Chase Bank, as trustee, as supplemented. The senior indenture and the subordinated indenture are substantially identical, except for certain covenants of ours and provisions relating to subordination. The senior indenture and the subordinated indenture are sometimes referred to herein collectively as the “indentures” and each individually as an “indenture,” and the trustees under each of the indentures are sometimes referred to herein collectively as the “trustees” and each individually as a “trustee.” The particular terms of the series of debt securities offered by any prospectus supplement, and the extent to which general provisions described below may apply to the offered series of debt securities, will be described in the prospectus supplement.

      The following summaries of the material terms and provisions of the indentures and the related debt securities are not complete and are subject to, and are qualified in their entirety by reference to, all provisions of the indentures, including the definitions of certain terms in the indentures and those terms to be made a part of the indentures by the Trust Indenture Act of 1939, as amended. Wherever we refer to particular articles, sections or defined terms of an indenture, without specific reference to an indenture, those articles, sections or defined terms are contained in all indentures.

      The indentures do not limit the aggregate principal amount of the debt securities which Platinum Holdings may issue under them and provide that Platinum Holdings may issue debt securities under them

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      Unless otherwise provided in a prospectus supplement, our senior debt securities will be unsecured obligations of Platinum Holdings, and will rank equally with all of Platinum Holdings other unsecured and unsubordinated indebtedness. The subordinated debt securities will be unsecured obligations of Platinum Holdings, subordinated in right of payment to the prior payment in full of all Senior Indebtedness (which term includes the senior debt securities) of Platinum Holdings as described below under “Subordination of the Subordinated Debt Securities” and in the applicable prospectus supplement.

      Because Platinum Holdings is a holding company, our rights and the rights of our creditors (including the holders of our debt securities) and shareholders to participate in distributions by certain of our subsidiaries upon that subsidiary’s liquidation or reorganization or otherwise would be subject to the prior claims of that subsidiary’s creditors, except to the extent that we may ourselves be a creditor with recognized claims against that subsidiary or our creditor may have the benefit of a guaranty from our subsidiary. None of our creditors has the benefit of a guaranty from any of our subsidiaries. The rights of our creditors (including the holders of our debt securities) to participate in the distribution of stock owned by us in certain of our subsidiaries, including our insurance subsidiaries, may also be subject to approval by certain insurance regulatory authorities having jurisdiction over such subsidiaries.

      Our ability to receive dividends and other distributions from our insurance company subsidiaries is limited by applicable law and regulation. See “Our Business — Regulation” in our Annual Report on Form 10-K for the year ended December 31, 2003 incorporated by reference in this prospectus. If we are unable to receive dividends or distributions from our insurance company subsidiaries, or if such dividends or distributions are limited, our ability to make payments owing with respect to the debt securities will be adversely affected.

      The prospectus supplement relating to the particular series of debt securities offered thereby will describe the following terms of the offered series of debt securities:

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      Platinum Holdings will have the ability under the indentures to “reopen” a previously issued series of debt securities and issue additional debt securities of that series or establish additional terms of that series. Platinum Holdings is also permitted to issue debt securities with the same terms as previously issued debt securities.

      Unless otherwise provided in the related prospectus supplement, principal, premium, interest and additional amounts, if any, with respect to any series of debt securities will be payable at the office or agency maintained by us for such purposes (initially the corporate trust office of the trustee). In the case of debt securities issued in registered form, interest may be paid by check mailed to the persons entitled thereto at their addresses appearing on the security register or by transfer to an account maintained by the payee with a bank located in the United States. Interest on debt securities issued in registered form will be payable on any interest payment date to the persons in whose names the debt securities are registered at the close of business on the regular record date with respect to such interest payment date. Interest on such debt securities which have a redemption date after a regular record date, and on or before the following interest payment date, will also be payable to the persons in whose names the debt securities are so registered. All paying agents initially designated by us for the debt securities will be named in the related prospectus supplement. We may at any time designate additional paying agents or rescind the designation of any paying agent or approve a change in the office through which any paying agent acts, except that we will be required to maintain a paying agent in each place where the principal of, any premium or interest on or any additional amounts with respect to the debt securities are payable.

      Unless otherwise provided in the related prospectus supplement, the debt securities may be presented for transfer (duly endorsed or accompanied by a written instrument of transfer, if so required by us or the security registrar) or exchanged for other debt securities of the same series (containing identical terms and provisions, in any authorized denominations, and of a like aggregate principal amount) at the office or agency maintained by us for such purposes (initially the corporate trust office of the trustee). Such transfer or exchange will be made without service charge, but we may require payment of a sum sufficient to cover any tax or other governmental charge and any other expenses then payable. We will not be required to (1) issue, register the transfer of, or exchange, the debt securities during a period beginning at the opening of business 15 days before the day of mailing of a notice of redemption of any such debt securities and ending at the close of business on the day of such mailing or (2) register the transfer of or exchange any debt security so selected for redemption in whole or in part, except the unredeemed portion of any debt security being redeemed in part. Any transfer agent (in addition to the security registrar) initially designated by us for any debt securities will be named in the related prospectus supplement. We may at any time designate additional transfer agents or rescind the designation of any transfer agent or approve a change in the office through which any transfer agent acts, except that we will be required to maintain a transfer agent in each place where the principal of, any premium or interest on or any additional amounts with respect to the debt securities are payable.

      Unless otherwise provided in the related prospectus supplement, the debt securities will be issued only in fully registered form without coupons in minimum denominations of $1,000 and any integral multiple thereof. The debt securities may be represented in whole or in part by one or more global debt securities registered in the name of a depositary or its nominee and, if so represented, interests in such global debt security will be shown on, and transfers thereof will be effected only through, records maintained by the designated depositary and its participants as described below. Where the debt securities of any series are issued in bearer form, the special restrictions and considerations, including special offering restrictions and special U.S. federal income tax considerations, applicable to such debt securities and to payment on and transfer and exchange of such debt securities will be described in the related prospectus supplement.

      The debt securities may be issued as original issue discount securities (bearing no fixed interest or bearing fixed interest at a rate which at the time of issuance is below specified market rates) to be sold at a substantial discount below their principal amount and may for various other reasons be considered to have original issue discount for U.S. federal income tax purposes. In general, original issue discount is included in the income of holders on a yield-to-maturity basis. Accordingly, depending on the terms of the debt securities, holders may be required to include amounts in income prior to the receipt thereof. Special U.S. federal income tax and

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      The debt securities may also be issued at a premium (issued for an amount in excess of the face amount of such securities). In general such bond premium would be amortizable over the term of the debt instrument and deductible by the holders for U.S. federal income tax purposes. Special U.S. federal income tax and other considerations applicable to securities issued at a premium will be described in the related prospectus supplement.

      If the purchase price of any debt securities is payable in one or more foreign currencies or currency units or if any debt securities are denominated in one or more foreign currencies or currency units or if the principal of, or any premium or interest on, or any additional amounts with respect to, any debt securities is payable in one or more foreign currencies or currency units, the restrictions, elections, certain U.S. federal income tax considerations, specific terms and other information with respect to such debt securities and such foreign currency or currency units will be set forth in the related prospectus supplement.

      We will comply with Section 14(e) under the Exchange Act, and any other tender offer rules under the Exchange Act which may then be applicable, in connection with any obligation of ours to purchase debt securities at the option of the holders. Any such obligation applicable to a series of debt securities will be described in the related prospectus supplement.

      Unless otherwise described in a prospectus supplement relating to any series of debt securities, the indentures do not contain any provisions that would limit our ability to incur indebtedness or that would afford holders of the debt securities protection in the event of a sudden and significant decline in our credit quality or a takeover, recapitalization or highly leveraged or similar transaction involving us. Accordingly, we could in the future enter into transactions that could increase the amount of indebtedness outstanding at that time or otherwise affect our capital structure or credit rating. You should refer to the prospectus supplement relating to a particular series of the debt securities for information regarding to any deletions from, modifications of or additions to the Events of Defaults described below or our covenants contained in the indentures, including any addition of a covenant or other provisions providing event risk or similar protection.

Conversion and Exchange

      The terms, if any, on which debt securities of any series are convertible into or exchangeable for common shares, preferred shares or other securities issued by us, property or cash, or a combination of any of the foregoing, will be set forth in the related prospectus supplement. Such terms may include provisions for conversion or exchange, either mandatory, at the option of the holder, or at our option, in which the securities, property or cash to be received by the holders of the debt securities would be calculated according to the factors and at such time as described in the related prospectus supplement. Any such conversion or exchange will comply with applicable Bermuda law, our memorandum of association and Bye-laws.

Optional Redemption

      Unless otherwise described in a prospectus supplement, relating to any debt securities, we may at our option, redeem any series of debt securities, in whole or in part, at any time at the redemption price. Unless otherwise described in a prospectus supplement, debt securities’ will not be subject to sinking fund or other mandatory redemption or to redemption or repurchase at the option of the holders upon a change of control, a change in management, an asset sale or any other specified event.

Selection and Notice

      Unless otherwise described in a prospectus supplement, we will send the holders of the debt securities to be redeemed a notice of redemption by first-class mail at least 30 and not more than 60 days prior to the date fixed for redemption. If we elect to redeem fewer than all the debt securities, unless otherwise agreed in a holders’ redemption agreement, the trustee will select in a fair and appropriate manner, including pro rata or by lot, the debt securities to be redeemed in whole or in part.

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      Unless we default in payment of the redemption price, the debt securities called for redemption shall cease to accrue any interest on or after the redemption date.

Consolidation, Amalgamation, Merger and Sale of Assets

      Unless otherwise described in a prospectus supplement, each indenture provides that Platinum Holdings may not (1) consolidate or amalgamate with or merge into any person or convey, transfer or lease our properties and assets as an entirety or substantially as an entirety to any person, or (2) permit any person to consolidate or amalgamate with or merge into Platinum Holdings, or convey, transfer or lease its properties and assets as an entirety or substantially as an entirety to us, unless (a) such person is a corporation or limited liability company organized and existing under the laws of the United States, any state thereof or the District of Columbia, Bermuda or any country which is, on the date of the indenture, a member of the Organization of Economic Cooperation and Development and will expressly assume, by supplemental indenture satisfactory in form to the trustee, the due and punctual payment of the principal of, any premium and interest on and any additional amounts with respect to the debt securities issued thereunder, and the performance of our obligations under the indenture and the debt securities issued thereunder; (b) immediately after giving effect to such transaction and treating any indebtedness which becomes an obligation of ours or of a designated subsidiary as a result of such transaction as having been incurred by us or such subsidiary at the time of such transaction, no event of default, and no event which after notice or lapse of time or both would become an event of default, will have happened and be continuing; and (c) certain other documents are delivered.

Certain Other Covenants

      Except as otherwise permitted under “Consolidation, Amalgamation, Merger and Sale of Assets” described above, we will do or cause to be done all things necessary to maintain in full force and effect our legal existence, rights (charter and statutory) and franchises. We are not, however, required to preserve any right or franchise if we determine that it is no longer desirable in the conduct of our business and the loss is not disadvantageous in any material respect to the holders of any debt securities. (Section 4.8 of the indenture)

Events of Default

      Unless we provide other or substitute Events of Default in a prospectus supplement, the following events will constitute an event of default under the applicable indenture with respect to a series of debt securities (whatever the reason for such event of default and whether it will be voluntary or involuntary or be effected by operation of law or pursuant to any judgment, decree or order of any court or any order, rule or regulation of any administrative or governmental body):

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      If an event of default with respect to the debt securities (other than an event of default described in clause (6) of the preceding paragraph) occurs and is continuing, either the trustee or the holders of at least 25% in principal amount of the outstanding debt securities by written notice as provided in the indenture may declare the principal amount of all outstanding debt securities to be due and payable immediately. An event of default described in clause (6) of the preceding paragraph will cause the principal amount and accrued interest to become immediately due and payable without any declaration or other act by the trustee or any holder. At any time after a declaration of acceleration has been made, but before a judgment or decree for payment of money has been obtained by the trustee, and subject to applicable law and certain other provisions of the indenture, the holders of a majority in aggregate principal amount of the debt securities may, under certain circumstances, rescind and annul such acceleration.

      Each indenture provides that, within 60 days after the occurrence of any event which is, or after notice or lapse of time or both would become, an event of default with respect to the debt securities, the trustee will transmit, in the manner set forth in the indenture and subject to the exceptions described below, notice of such default to the holders of the debt securities unless such default has been cured or waived. However, except in the case of a default in the payment of principal of, or premium, if any, or interest on, or additional amounts with respect to, any debt securities, the trustee may withhold such notice if and so long as the board, executive committee or a trust committee of directors and/or responsible officers of the trustee in good faith determine that the withholding of such notice is in the best interest of the holders of the debt securities.

      If an event of default occurs, has not been waived and is continuing with respect to the debt securities, the trustee may in its discretion proceed to protect and enforce its rights and the rights of the holders of the debt securities by all appropriate judicial proceedings. Each indenture provides that, subject to the duty of the trustee during any default to act with the required standard of care, the trustee will be under no obligation to exercise any of its rights or powers under such indenture at the request or direction of any of the holders of the debt securities, unless such holders shall have offered to the trustee reasonable indemnity. Subject to such provisions for the indemnification of the trustee, and subject to applicable law and certain other provisions of the indenture, the holders of a majority in aggregate principal amount of the outstanding debt securities will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or exercising any trust or power conferred on the trustee, with respect to the debt securities.

      Under the Companies Act, any payment or other disposition of property made by us within six months prior to the commencement of our winding up will be invalid if made with the intent to fraudulently prefer one or more of our creditors at a time that we were unable to pay our debts as they became due.

Modification and Waiver

      We and the trustee may modify or amend each indenture with the consent of the holders of not less than a majority in aggregate principal amount outstanding of a series of debt securities affected by the amendment or modification; provided, however, that no such modification or amendment may, without the consent of the holder of each outstanding debt security affected thereby:

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      In addition, no supplemental indenture may directly or indirectly modify or eliminate the subordination provisions of the subordinated indentures in any manner which might terminate or impair the subordination of the subordinated debt securities to Senior Indebtedness without the prior written consent of the holders of the Senior Indebtedness.

      We and the trustee may modify or amend each indenture and the series of debt securities without the consent of any holder in order to, among other things:

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      The holders of at least a majority in aggregate principal amount of the series of debt securities may, on behalf of the holders of the debt securities, waive compliance by us with certain restrictive provisions of the indenture. (Section 4.9 of the indenture) The holders of not less than a majority in aggregate principal amount of the series of debt securities may, on behalf of the holders of the debt securities, waive any past default and its consequences under the indenture with respect to the series of debt securities, except a default (1) in the payment of principal of, any premium or interest on or any additional amounts with respect to the series of debt securities or (2) in respect of a covenant or provision of the indenture that cannot be modified or amended without the consent of the holder of each debt security. (Section 6.10 of the indenture)

      Under each indenture, we are required to furnish the trustee annually a statement as to performance by us of certain of our obligations under the indenture and as to any default in such performance. We are also required to deliver to the trustee, within five days after occurrence thereof, written notice of any event of default or any event which after notice or lapse of time or both would constitute an event of default under clause (3) in “— Events of Default” described above. (Section 4.10 of the indenture)

Discharge, Defeasance and Covenant Defeasance

      We may discharge certain obligations to holders of the debt securities that have not already been delivered to the trustee for cancellation and that either have become due and payable or will become due and payable within one year (or called for redemption within one year) by depositing with the trustee, in trust, funds in U.S. dollars or Government Obligations (as defined below) in an amount sufficient to pay the entire indebtedness on the debt securities with respect to principal and any premium, interest and additional amounts to the date of such deposit (if the debt securities have become due and payable) or with respect to principal, any premium and interest to the maturity or redemption date thereof, as the case may be. (Section 12.1 of the indenture)

      Each indenture provides that, unless the provisions of Section 12.2 of such indenture are made inapplicable to the debt securities pursuant to Section 3.1 of the indenture, we may elect either (1) to defease and be discharged from any and all obligations with respect to the debt securities (except for, among other things, the obligation to pay principal, interest and additional amounts, if any, upon the occurrence of certain events of taxation, assessment or governmental charge with respect to payments on the debt securities and other obligations to register the transfer or exchange of the debt securities, to replace temporary or mutilated, destroyed, lost or stolen debt securities, to maintain an office or agency with respect to the debt securities and to hold moneys for payment in trust) (“defeasance”) or (2) to be released from our obligations with respect to the debt securities under certain covenants and any omission to comply with such obligations will not constitute a default or an event of default with respect to the debt securities (“covenant defeasance”). Defeasance or covenant defeasance, as the case may be, will be conditioned upon the irrevocable deposit by us with the trustee, in trust, of an amount in U.S. dollars, or Government Obligations, or both, applicable to such debt securities which through the scheduled payment of principal and interest in accordance with their terms will provide money in an amount sufficient to pay the principal of, any premium and interest on the debt securities on the scheduled due dates or any prior redemption date. (Section 12.2 of the indenture)

      Such a trust may only be established if, among other things:

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      “Government Obligations” means debt securities which are (1) direct obligations of the United States of America for the payment of which its full faith and credit is pledged or (2) obligations of a Person controlled or supervised by and acting as an agency or instrumentality of the United States of America the timely payment of which is unconditionally guaranteed as a full faith and credit obligation by the United States of America which, in the case of clauses (1) and (2), are not callable or redeemable at the option of the issuer or issuers thereof, and will also include a depository receipt issued by a bank or trust company as custodian with respect to any such Government Obligation or a specific payment of interest on or principal of or any other amount with respect to any such Government Obligation held by such custodian for the account of the holder of such depository receipt, provided that (except as required by law) such custodian is not authorized to make any deduction from the amount payable to the holder of such depository receipt from any amount received by the custodian with respect to the Government Obligation or the specific payment of interest on or principal of or any other amount with respect to the Government Obligation evidenced by such depository receipt. (Section 1.1 of the indenture)

      In the event we effect covenant defeasance with respect to the debt securities and the debt securities are declared due and payable because of the occurrence of any event of default other than an event of default with respect to any covenant as to which there has been covenant defeasance, the Government Obligations on deposit with the trustee will be sufficient to pay amounts due on the debt securities at the time of the stated maturity or redemption date but may not be sufficient to pay amounts due on the debt securities at the time of the acceleration resulting from such event of default. However, we would remain liable to make payment of such amounts due at the time of acceleration.

Payment of Additional Amounts

      Unless otherwise described in a prospectus supplement, we will make all payments of principal of and premium, if any, interest and any other amounts on, or in respect of, the debt securities without withholding or deduction at source for, or on account of, any present or future taxes, fees, duties, assessments or governmental charges of whatever nature imposed or levied by or on behalf of Bermuda or any other jurisdiction in which we are organized (a “taxing jurisdiction”) or any political subdivision or taxing authority thereof or therein, unless such taxes, fees, duties, assessments or governmental charges are required to be withheld or deducted by (x) the laws (or any regulations or rulings promulgated thereunder) of a taxing jurisdiction or any political subdivision or taxing authority thereof or therein or (y) an official position regarding the application, administration, interpretation or enforcement of any such laws, regulations or rulings (including, without limitation, a holding by a court of competent jurisdiction or by a taxing authority in a taxing jurisdiction or any political subdivision thereof). If a withholding or deduction at source is required, we will, subject to certain limitations and exceptions described below, pay to the holder of any debt security such additional amounts as may be necessary so that every net payment of principal, premium, if any, interest or any other amount made to such holder, after the withholding or deduction, will not be less than the amount provided for in such debt security or in the indenture to be then due and payable.

      We will not be required to pay any additional amounts for or on account of:

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      In addition, we will not pay additional amounts with respect to any payment of principal of, or premium, if any, interest or any other amounts on, any such debt security to any holder who is a fiduciary or partnership or other than the sole beneficial owner of such debt security if such payment would be required by the laws of the relevant taxing jurisdiction (or any political subdivision or relevant taxing authority thereof or therein) to be included in the income for tax purposes of a beneficiary or partner or settlor with respect to such fiduciary or a member of such partnership or a beneficial owner to the extent such beneficiary, partner or settlor would not have been entitled to such additional amounts had it been the holder of the debt security. (Section 4.4 of the indenture)

Redemption for Tax Purposes

      Unless otherwise described in a prospectus supplement, we may redeem the debt securities at our option, in whole but not in part, at a redemption price equal to 100% of the principal amount, together with accrued and unpaid interest and additional amounts, if any, to the date fixed for redemption, at any time we receive an opinion of counsel that as a result of (1) any change in or amendment to the laws or treaties (or any regulations or rulings promulgated under these laws or treaties) of Bermuda or any taxing jurisdiction (or of any political subdivision or taxation authority affecting taxation) or any change in the application or official interpretation of such laws, regulations or rulings, or (2) any action taken by a taxing authority of Bermuda or any taxing jurisdiction (or any political subdivision or taxing authority affecting taxation) which action is generally applied or is taken with respect to the Company, or (3) a decision rendered by a court of competent jurisdiction in Bermuda or any taxing jurisdiction (or any political subdivision) whether or not such decision was rendered with respect to us, there is a substantial probability that we will be required as of the next interest payment date to pay additional amounts with respect to the debt securities as provided in “Payment of Additional Amounts” above and such requirements cannot be avoided by the use of reasonable measures (consistent with practices and interpretations generally followed or in effect at the time such measures could be taken) then available. If we elect to redeem the debt securities under this provision, we will give written notice of such election to the trustee and the holders of the debt securities.

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      Interest on the debt securities will cease to accrue unless we default in the payment of the redemption price. (Section 4.5 of the indenture)

Global Securities

      The debt securities of a series may be issued in whole or in part in the form of one or more global debt securities that will be deposited with, or on behalf of, a depositary identified in the prospectus supplement relating to such series.

      The specific terms of the depositary arrangement with respect to a series of the debt securities will be described in the prospectus supplement relating to such series. We anticipate that the following provisions will apply to all depositary arrangements.

      Upon the issuance of a global security, the depositary for such global security or its nominee will credit, on its book-entry registration and transfer system, the respective principal amounts of the debt securities represented by such global security. Such accounts will be designated by the underwriters or agents with respect to such debt securities or by us if such debt securities are offered and sold directly by us. Ownership of beneficial interests in a global security will be limited to persons that may hold interests through participants. Ownership of beneficial interests in such global security will be shown on, and the transfer of that ownership will be effected only through, records maintained by the depositary or its nominee (with respect to interests of participants) and on the records of participants (with respect to interests of persons other than participants). The laws of some states require that certain purchasers of securities take physical delivery of such securities in definitive form. Such limits and such laws may impair the ability to transfer beneficial interests in a global security.

      So long as the depositary for a global security, or its nominee, is the registered owner of such global security, such depositary or such nominee, as the case may be, will be considered the sole owner or holder of the debt securities represented by such global security for all purposes under the applicable indenture. Except as described below, owners of beneficial interests in a global security will not be entitled to have the debt securities of the series represented by such global security registered in their names and will not receive or be entitled to receive physical delivery of the debt securities of that series in definitive form.

      Principal of, any premium and interest on, and any additional amounts with respect to, the debt securities registered in the name of a depositary or its nominee will be made to the depositary or its nominee, as the case may be, as the registered owner of the global security representing such debt securities. None of the trustee, any paying agent, the security registrar or us will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests of the global security for such debt securities or for maintaining, supervising or reviewing any records relating to such beneficial ownership interests.

      We expect that the depositary for a series of the debt securities or its nominee, upon receipt of any payment with respect to such debt securities, will credit immediately participants’ accounts with payments in amounts proportionate to their respective beneficial interest in the principal amount of the global security for such debt securities as shown on the records of such depositary or its nominee. We also expect that payments by participants to owners of beneficial interests in such global security held through such participants will be governed by standing instructions and customary practices, as is now the case with securities held for the accounts of customers registered in “street name,” and will be the responsibility of such participants.

      The indentures provide that if:

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      Such definitive debt securities will be registered in such name or names as the depositary shall instruct the trustee. (Section 3.5 of the indenture). It is expected that such instructions may be based upon directions received by the depositary from participants with respect to ownership of beneficial interests in global securities.

Governing Law

      Each indenture and the debt securities will be governed by, and construed in accordance with, the laws of the State of New York applicable to agreements made or instruments entered into and, in each case, performed in that state.

Information Concerning the Trustee

      Unless otherwise specified in the applicable prospectus supplement, JPMorgan Chase Bank is to be the trustee and paying agent under each indenture and is one of a number of banks with which Platinum and its subsidiaries maintain banking relationships in the ordinary course of business.

CERTAIN PROVISIONS APPLICABLE TO SUBORDINATED DEBT SECURITIES

Subordination of the Subordinated Debt Securities

      The subordinated debt securities will, to the extent set forth in the subordinated indenture, be subordinate in right of payment to the prior payment in full of all Senior Indebtedness. In the event of:

then and in any such event the holders of Senior Indebtedness will be entitled to receive payment in full of all amounts due or to become due on or in respect of all Senior Indebtedness, or provision will be made for such payment in cash, before the holders of the subordinated debt securities are entitled to receive or retain any payment on account of principal of, or any premium or interest on, or any additional amounts with respect to, subordinated debt securities, and to that end the holders of Senior Indebtedness will be entitled to receive, for application to the payment thereof, any payment or distribution of any kind or character, whether in cash, property or securities, including any such payment or distribution which may be payable or deliverable by reason of the payment of any other Indebtedness of ours being subordinated to the payment of subordinated debt securities, which may be payable or deliverable in respect of subordinated debt securities in any such case, proceeding, dissolution, liquidation or other winding up event.

      By reason of such subordination, in the event of our liquidation or insolvency, holders of Senior Indebtedness and holders of other obligations of ours that are not subordinated to Senior Indebtedness may recover more, ratably, than the holders of subordinated debt securities.

      Subject to the payment in full of all Senior Indebtedness, the rights of the holders of subordinated debt securities will be subrogated to the rights of the holders of Senior Indebtedness to receive payments or distributions of cash, property or securities of ours applicable to such Senior Indebtedness until the principal of, any premium and interest on, and any additional amounts with respect to, subordinated debt securities have been paid in full.

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      No payment of principal (including redemption and sinking fund payments) of or any premium or interest on or any additional amounts with respect to the subordinated debt securities, or payments to acquire such securities (other than pursuant to their conversion), may be made (1) if any Senior Indebtedness of ours is not paid when due and any applicable grace period with respect to such default has ended and such default has not been cured or waived or ceased to exist, or (2) if the maturity of any Senior Indebtedness of ours has been accelerated because of a default. The subordinated indenture does not limit or prohibit us from incurring additional Senior Indebtedness, which may include Indebtedness that is senior to subordinated debt securities, but subordinate to our other obligations. The senior debt securities will constitute Senior Indebtedness under the subordinated indenture.

      The term “Senior Indebtedness” means all Indebtedness of ours outstanding at any time, except:

      Such Senior Indebtedness will continue to be Senior Indebtedness and be entitled to the benefits of the subordination provisions irrespective of any amendment, modification or waiver of any term of such Senior Indebtedness.

      The subordinated indenture provides that the foregoing subordination provisions, insofar as they relate to any particular issue of subordinated debt securities, may be changed prior to such issuance. Any such change would be described in the related prospectus supplement.

DESCRIPTION OF THE WARRANTS TO PURCHASE

      The following statements with respect to the common share warrants and preference share warrants are summaries of, and subject to, the detailed provisions of a share warrant agreement to be entered into by us and a share warrant agent to be selected at the time of issue. The particular terms of any warrants offered by any prospectus supplement, and the extent to which the general provisions described below may apply to the offered securities, will be described in the prospectus supplement.

General

      The share warrants, evidenced by share warrant certificates, may be issued under the share warrant agreement independently or together with any other securities offered by any prospectus supplement and may be attached to or separate from such other offered securities. If share warrants are offered, the related prospectus supplement will describe the designation and terms of the share warrants, including without limitation the following:

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      The common shares or preferred shares issuable upon exercise of the share warrants will, when issued in accordance with the share warrant agreement, be fully paid and nonassessable.

Exercise of Stock Warrants

      Share warrants may be exercised by surrendering to the share warrant agent the share warrant certificate with the form of election to purchase on the reverse thereof duly completed and signed by the warrantholder, or its duly authorized agent (such signature to be guaranteed by a bank or trust company, by a broker or dealer which is a member of the National Association of Securities Dealers, Inc. or by a member of a national securities exchange), indicating the warrantholder’s election to exercise all or a portion of the share warrants evidenced by the certificate. Surrendered share warrant certificates will be accompanied by payment of the aggregate exercise price of the share warrants to be exercised, as set forth in the related prospectus supplement, in lawful money of the United States, unless otherwise provided in the related prospectus supplement. Upon receipt thereof by the share warrant agent, the share warrant agent will requisition from the transfer agent for the common shares or the preferred shares, as the case may be, for issuance and delivery to or upon the written order of the exercising warrantholder, a certificate representing the number of common shares or preferred shares purchased. If less than all of the share warrants evidenced by any share warrant certificate are exercised, the share warrant agent will deliver to the exercising warrantholder a new share warrant certificate representing the unexercised share warrants.

Antidilution and Other Provisions

      The exercise price payable and the number of common shares or preferred shares purchasable upon the exercise of each share warrant and the number of share warrants outstanding will be subject to adjustment in certain events which will be described in a prospectus supplement. These may include the issuance of a stock dividend to holders of common shares or preferred shares, respectively, or a combination, subdivision or reclassification of common shares or preferred shares, respectively. In lieu of adjusting the number of common shares or preferred shares purchasable upon exercise of each share warrant, we may elect to adjust the number of share warrants. No adjustment in the number of shares purchasable upon exercise of the share warrants will be required until cumulative adjustments require an adjustment of at least 1% thereof. We may, at our option, reduce the exercise price at any time. No fractional shares will be issued upon exercise of share warrants, but we will pay the cash value of any fractional shares otherwise issuable. Notwithstanding the foregoing, in case of our consolidation, merger, or sale or conveyance of our property as an entirety or substantially as an entirety, the holder of each outstanding share warrant shall have the right to the kind and amount of shares of stock and

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No Rights as Shareholders

      Holders of share warrants will not be entitled, by virtue of being such holders, to vote, to consent, to receive dividends, to receive notice as shareholders with respect to any meeting of shareholders for the election of our directors or any other matter, or to exercise any rights whatsoever as our shareholders.

DESCRIPTION OF THE WARRANTS TO PURCHASE DEBT SECURITIES

      The following statements with respect to the debt warrants are summaries of, and subject to, the detailed provisions of a debt warrant agreement to be entered into by us and a debt warrant agent to be selected at the time of issue. The debt warrant agreement may include or incorporate by reference standard warrant provisions substantially in the form of the Standard Debt Warrant Provisions filed as an exhibit to the registration statement of which this prospectus forms a part. The particular terms of any warrants offered by any prospectus supplement, and the extent to which the general provisions described below may apply to the offered securities, will be described in the prospectus supplement.

General

      The debt warrants, evidenced by debt warrant certificates, may be issued under the debt warrant agreement independently or together with any other securities offered by any prospectus supplement and may be attached to or separate from such other offered securities. If debt warrants are offered, the related prospectus supplement will describe the designation and terms of the debt warrants, including without limitation the following:

      Warrantholders will not have any of the rights of holders of debt securities, including the right to receive the payment of principal of, any premium or interest on, or any additional amounts with respect to, the debt securities or to enforce any of the covenants of the debt securities or the applicable indenture except as otherwise provided in the applicable indenture.

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Exercise of Debt Warrants

      Debt warrants may be exercised by surrendering the debt warrant certificate at the office of the debt warrant agent, with the form of election to purchase on the reverse side of the debt warrant certificate properly completed and executed (with signature(s) guaranteed by a bank or trust company, by a broker or dealer which is a member of the National Association of Securities Dealers, Inc. or by a member of a national securities exchange), and by payment in full of the exercise price, as set forth in the related prospectus supplement. Upon the exercise of debt warrants, we will issue the debt securities in authorized denominations in accordance with the instructions of the exercising warrantholder. If less than all of the debt warrants evidenced by the debt warrant certificate are exercised, a new debt warrant certificate will be issued for the remaining number of debt warrants.

DESCRIPTION OF THE PURCHASE CONTRACTS AND THE PURCHASE UNITS

      We may issue purchase contracts, obligating holders to purchase from us, and obligating us to sell to the holders, a specified number of our common shares, preferred shares, debt securities or securities of third parties, a basket of such securities, an index or indices of such securities or any combination of the above, as specified in the applicable prospectus supplement, at a future date or dates. The price per security may be fixed at the time the purchase contracts are issued or may be determined by reference to a specific formula set forth in the purchase contracts and to be described in the applicable prospectus supplement. The purchase contracts may be issued separately or as a part of purchase units consisting of a purchase contract and, as security for the holder’s obligations to purchase the securities under the purchase contracts, either:

      The applicable prospectus supplement will specify the securities that will secure the holder’s obligations to purchase securities under the applicable purchase contract. Unless otherwise described in a prospectus supplement, the securities related to the purchase contracts securing the holders’ obligations to purchase securities will be pledged to a collateral agent, for our benefit, under a pledge agreement. The pledged securities will secure the obligations of holders of purchase contracts to purchase securities under the related purchase contracts. The rights of holders of purchase contracts to the related pledged securities will be subject to our security interest in those pledged securities. That security interest will be created by the pledge agreement. No holder of purchase contracts will be permitted to withdraw the pledged securities related to such purchase contracts from the pledge arrangement except upon the termination or early settlement of the related purchase contracts. Subject to that security interest and the terms of the purchase contract agreement and the pledge agreement, each holder of a purchase contract will retain full beneficial ownership of the related pledged securities.

      The purchase contracts may require us to make periodic payments to the holders of the purchase units or vice versa, and such payments may be unsecured or prefunded on some basis. The purchase contracts may require holders to secure their obligations in a specified manner and in certain circumstances we may deliver newly issued prepaid purchase contracts upon release to a holder of any collateral securing such holder’s obligations under the original purchase contract.

      The applicable prospectus supplement will describe the terms of any purchase contracts or purchase units and, if applicable, prepaid purchase contracts.

      Except as described in a prospectus supplement, the collateral agent will, upon receipt of distributions on the pledged securities, distribute those payments to us or a purchase contract agent, as provided in the pledge agreement. The purchase contract agent will in turn distribute payments it receives as provided in the purchase contract.

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SELLING SHAREHOLDERS

      The selling shareholders may from time to time on one or more occasions offer and sell any or all of their common shares that are registered under this prospectus. The registration of the selling shareholders’ common shares does not necessarily mean that the selling shareholders will offer or sell any of their shares.

      The selling shareholders may sell, transfer or otherwise dispose of some or all of their common shares, including common shares and other securities of Platinum not covered by this prospectus, in transactions exempt from the registration requirements of the Securities Act of 1933, including in open-market transactions in reliance on Rule 144 under the Securities Act. We will update, amend or supplement this prospectus from time to time to update the disclosure in this section as may be required.

      All expenses incurred with the registration of Platinum common shares owned by the selling shareholders will be borne by us; provided that we will not be obligated to pay any legal expenses of the selling shareholders in connection with such registration.

      The following table sets forth information as of March 1, 2004 regarding beneficial ownership of common shares and the applicable voting rights attached to such share ownership in accordance with our Bye-laws by the selling shareholder that may offer common shares pursuant to this registration statement.

For a description of the relationships between St. Paul, RenaissanceRe and us, see “Related Party Transactions.”

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RELATED PARTY TRANSACTIONS

Transactions With St. Paul and its Subsidiaries

      Concurrently with the completion of the Company’s initial public offering on November 1, 2002, the Company issued 6,000,000 common shares (or 14% of the then outstanding common shares) to St. Paul in a private placement pursuant to the Formation Agreement. The voting power of these common shares is limited to 9.9% of the voting power of the outstanding common shares, pursuant to the Bye-laws of the Company. St. Paul also received an option to purchase up to 6,000,000 additional common shares at any time during the ten years following the Company’s initial public offering at a price of $27.00 per share (the “St. Paul Option”). In return for the common shares and the St. Paul Option, St. Paul contributed to the Company cash in the amount of $122 million and substantially all of the 2002 reinsurance business and related assets of the reinsurance underwriting segment of St. Paul (“St. Paul Re”), including all of the outstanding capital stock of Platinum US. Among the fixed assets transferred were furniture, equipment, systems and software, and the intangible assets included broker lists, contract renewal rights and licenses. The Formation Agreement contains provisions regarding indemnification of each of St. Paul and the Company by the other, restrictions on St. Paul regarding competition with the Company and the transfer or acquisition of common shares in certain circumstances, and requirements relating to pre-emptive rights and participation in common share buy-back programs. The Formation Agreement provided that the Company and its subsidiaries enter into several agreements with St. Paul and its subsidiaries, as described below.

      The Company entered into a Registration Rights Agreement with St. Paul as of November 1, 2002 and a related letter agreement dated March 22, 2004, pursuant to which St. Paul has the right to require the Company, subject to certain specified exceptions, on three occasions to register under the Securities Act, any common shares owned by St. Paul or its affiliates for sale in a public offering. Pursuant to this agreement, the Company has also agreed to use its reasonable best efforts to enable St. Paul from and after the third anniversary of the completion of the Company’s initial public offering to distribute the common shares it beneficially owns in an offering on a continuous or delayed basis pursuant to a registration statement under the Securities Act. After November 1, 2007, St. Paul will have the right to an additional two demand registrations if St. Paul beneficially owns more than 9.9% of the common shares then outstanding. Each demand must include a number of common shares with a market value equal to at least $50 million, except that this limitation will not apply to St. Paul’s last demand registration. Pursuant to the letter agreement, each of St. Paul and the Company have agreed that their respective rights, duties and obligations with regard to the registration, offering and sale of St. Paul’s common shares under the registration statement of which this prospectus forms a part shall be as if the registration statement had been filed pursuant to a demand request under the Registration Rights Agreement.

      Certain subsidiaries of the Company entered into several quota share retrocession agreements with subsidiaries of St. Paul, pursuant to which St. Paul’s subsidiaries transferred the liabilities, related assets and rights and risks under substantially all of the reinsurance contracts entered into by St. Paul’s subsidiaries on or after January 1, 2002, excluding certain liabilities relating to the flooding in Europe in August 2002 and business underwritten in London for certain financial services companies (the “Quota Share Retrocession Agreements”). These agreements provided for the transfer to subsidiaries of the Company of cash and other assets aggregating approximately $485,687,000, which represents substantially all of the existing 2002 underwriting year loss reserves, excluding certain liabilities retained by St. Paul, allocated loss adjustment expense reserves, other reserves related to non-traditional reinsurance treaties, unearned premium reserves (subject to agreed upon adjustments) and other related reserves, which relate to contracts entered into on and after January 1, 2002, as of the date of the transfer and 100% of future premiums (less any ceding commission under the Quota Share Retrocession Agreements) associated with the transferred reinsurance contracts relating to periods after the date of the transfer. Trusts have been established and funded to secure Platinum US’s retrocession obligations to St. Paul’s subsidiaries.

      Platinum US and St. Paul Fire and Marine Insurance Company, a wholly owned subsidiary of St. Paul (“St. Paul Fire and Marine”), entered into a US Underwriting Management Agreement dated as of November 1, 2002. Pursuant to this agreement, Platinum US has authority to write renewals of certain non-

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      In addition, St. Paul Re UK, St. Paul Management Limited and Platinum UK entered into a UK Business Transfer Agreement under which Platinum UK acquired the reinsurance business of St. Paul Re UK, together with the associated customer lists and goodwill (other than the assumption of liability for, or the management of, existing reinsurance contracts entered into by St. Paul Re UK on or prior to November 1, 2002). Platinum UK is entitled to write reinsurance business for its own account and benefit in succession to St. Paul Re UK. In consideration for the transfer, a portion of the St. Paul Option, covering 894,260 common shares with an aggregate exercise price of $8,119,881, was allocated to St. Paul Re UK.

      The Company and Platinum UK entered into Master Services Agreements with St. Paul and St. Paul Re UK pursuant to which St. Paul and its subsidiaries provide certain services, including accounting, payroll administration, human resources management and systems support, at cost until the Company and Platinum UK deem it no longer necessary. Both of these Master Services Agreements, which originally were scheduled to terminate on June 30, 2003, were amended by the parties to terminate on June 30, 2004 with respect to certain services. The Company and Platinum UK are required to pay St. Paul and St. Paul Re UK a total of $181,506 for services provided in 2003 under the Master Services Agreements. The Company and Platinum UK also entered into Run-off Services Agreements with St. Paul and St. Paul Re UK, pursuant to which the Company and Platinum UK, for a period of up to two years following completion of the Company’s initial public offering, provide St. Paul and St. Paul Re UK with specified services at cost in administering the run-off of certain reinsurance contracts. St. Paul and St. Paul Re UK paid the Company and Platinum UK approximately $605,236 for services provided in 2003 under the Run-off Services Agreements.

      Pursuant to the Employee Benefits and Compensation Matters Agreement, St. Paul transferred certain of its employees to Platinum US. The agreement provides for the allocation of assets and liabilities and certain other agreements with respect to employee compensation and benefit plans. The agreement provides that St. Paul will reimburse Platinum US pro rata for any retention bonuses that are paid to certain employees of the Company.

      Platinum UK is a party to a sublease agreement with St. Paul Re UK under which Platinum UK subleases office space in London at a rate equivalent to St. Paul’s cost. A total of $710,000 is payable under this agreement for 2003.

      Platinum US entered into an Aggregate Excess of Loss Retrocession Agreement with Mountain Ridge Insurance Company, a St. Paul subsidiary, on June 11, 2003. This Agreement related to an underlying agreement with Liberty Mutual which, in turn, was reinsured by Platinum US under a 100% Quota Share Retrocession Agreement with Mountain Ridge Insurance Company.

      Platinum US has entered into several novation and other agreements with St. Paul and various ceding insurance companies, whereby Platinum has replaced St. Paul as the reinsurer on the respective contracts. In certain cases, these contracts were originally issued by St. Paul Fire and Marine because Platinum US was not authorized as a reinsurer in Wisconsin. Several novation agreements were entered into after Platinum US became authorized in Wisconsin.

      Platinum UK entered into an Excess of Loss Reinsurance contract with XL Re on July 1, 2003 that replaced an existing contract between XL Re and St Paul. This contract includes a provision whereby St. Paul receives a commission as compensation for forfeiting a $5.65 million deficit premium that would have been paid to St. Paul if the existing contract had simply been terminated.

      Platinum Bermuda is one of several reinsurers participating on five excess-of-loss reinsurance contracts and a variable quota share reinsurance contract with certain subsidiaries of St. Paul relating to contract surety

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Transactions with RenaissanceRe and its Subsidiaries

      Concurrently with the completion of the Company’s initial public offering, the Company sold 3,960,000 common shares to RenaissanceRe at a price of $22.50 per share less the underwriting discount (the “RenaissanceRe Investment”) in a private placement pursuant to the Investment Agreement. In addition, RenaissanceRe received an option to purchase up to 2,500,000 additional common shares at any time during the ten years following the Company’s initial public offering at a purchase price of $27.00 per share. The Investment Agreement provides that, for so long as RenaissanceRe beneficially owns common shares representing at least 62.5% of the common shares purchased pursuant to the Investment Agreement, one qualified person designated by RenaissanceRe, who is reasonably acceptable to the Company, but not an officer, director or employee of RenaissanceRe or any of its subsidiaries, will be nominated by the Company for election as a director of the Company at each shareholder meeting at which directors are elected and the Company shall use commercially reasonable efforts to cause this director’s appointment to the Executive Committee and, subject to applicable law, rules or regulations, the Governance Committee of the Board of Directors of the Company. The Investment Agreement also provides that, for so long as RenaissanceRe beneficially owns common shares representing at least 62.5% of the common shares purchased pursuant to the Investment Agreement, RenaissanceRe will have the right to designate a representative to attend (but not to vote at) meetings of the Board of Directors and to receive notices, agendas, minutes and all other materials distributed to participants at such meetings.

      The Company and RenaissanceRe entered into a Transfer Restrictions, Registration Rights and Standstill Agreement as of November 1, 2002, pursuant to which, prior to November 1, 2003, RenaissanceRe could not transfer any interest in the common shares it purchased pursuant to the Investment Agreement except under certain conditions. Under this agreement, RenaissanceRe has the right to require the Company, subject to certain specified exceptions, on four occasions to register under the Securities Act any Common Shares owned by RenaissanceRe or its affiliates for sale in a public offering beginning as of November 1, 2003. The Company has also agreed to use its reasonable best efforts to enable RenaissanceRe, from and after the third anniversary of the completion of the Company’s initial public offering, to distribute the common shares it beneficially owns in an offering on a continuous or delayed basis pursuant to a registration statement under the Securities Act. After November 1, 2007, RenaissanceRe will have the right to an additional two demand registrations if RenaissanceRe beneficially owns more than 9.9% of the common shares then outstanding. Each demand must include a number of common shares with a market value equal to at least $50 million, except that this limitation will not apply to RenaissanceRe’s last demand registration. This agreement also contains provisions regarding indemnification of each of RenaissanceRe and the Company by the other, restrictions on RenaissanceRe regarding the acquisition of common shares in certain circumstances, and requirements relating to pre-emptive rights and participation in common share buy-back programs.

      The Company entered into a five-year Services and Capacity Reservation Agreement with RenaissanceRe, effective October 1, 2002, pursuant to which RenaissanceRe provides services to the subsidiaries of the Company in connection with its property catastrophe book of business. At the Company’s request, RenaissanceRe will analyze the Company’s property catastrophe treaties and contracts and will assist the Company in measuring risk and managing the Company’s aggregate catastrophe exposures. Based upon such analysis, RenaissanceRe will furnish quotations at the Company’s request for rates for non-marine property catastrophe retrocessional coverage with aggregate limits up to $100 million annually, either on an excess-of-loss or proportional basis. The Company and RenaissanceRe may then enter into retrocessional agreements on the basis of the quotations. The fee for the coverage commitment and the services provided by RenaissanceRe under this agreement is $4 million at inception and at each anniversary, adjusted to 3.5% of the Company’s gross written non-marine non-finite property catastrophe premium for the previous annual period, if and to the extent such amount is greater than the fee paid in such previous annual period. Either party may terminate this agreement if the other is deemed impaired or insolvent by applicable regulatory or judicial authorities or is

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      Platinum Bermuda and Platinum US have each entered into substantially similar Referral Agreements with Renaissance Underwriting Managers Ltd. (“RUM”), a subsidiary of RenaissanceRe, effective November 1, 2002 (collectively, the “Referral Agreements”), pursuant to which RUM provides referrals of treaty and facultative reinsurance contracts to Platinum Bermuda and Platinum US (the “Referred Contracts”). Under the Referral Agreements, Platinum Bermuda and Platinum US each have the opportunity to quote on Referred Contracts that would not otherwise be presented to Platinum Bermuda or Platinum US in the normal course. Under each of the Referral Agreements, Platinum Bermuda and Platinum US pay RUM an annual finder’s fee and, in certain circumstances, a profit commission for Referred Contracts actually bound by Platinum Bermuda or Platinum US in accordance with formulas set forth in the Referral Agreements. Under the Referral Agreements, RUM may elect, at the time it refers a Referred Contract, to cause Platinum Bermuda or Platinum US to retrocede up to 30% of such Referred Contract actually bound by Platinum Bermuda or Platinum US (the “RenRe Retro Share”). The finder’s fee and any profit commission due to RUM under each Referral Agreement is reduced by the amount of the RenRe Retro Share. The RenRe Retro Share may be subject to an aggregate loss ratio cap that will limit the maximum liability of RenaissanceRe to 225% of Gross Premium Written (as defined in the Referral Agreement) for each annual period. The Referral Agreements expire on October 31, 2007. No amounts were paid to RUM by Platinum US under its Referral Agreement in 2003. Platinum Bermuda paid RUM $400,283 under its Referral Agreement in 2003.

      Platinum US entered into an Excess of Loss Contract with RenaissanceRe effective as of June 11, 2003, where the loss index is based on a property catastrophe program purchased by Platinum US. Under this contract, RenaissanceRe is liable for 50% of all premiums (plus a 2% override) and is entitled to 50% of any loss recoveries under the indexed property catastrophe program.

      Platinum US is party to two property catastrophe excess of loss programs with the Glencoe Group of Companies, which are affiliates of RenaissanceRe. Platinum has a 5% participation across four layers of reinsurance on one program and a 15% participation on the other program.

CERTAIN TAX CONSIDERATIONS

      The following discussion of the taxation of Platinum Holdings, Platinum US, Platinum UK, Platinum Bermuda and Platinum Ireland and the taxation of our shareholders is based upon current law. Legislative, judicial or administrative changes may occur which could affect this discussion, possibly on a retroactive basis. This discussion does not address special classes of shareholders, such as shareholders that own directly, or indirectly through certain foreign entities or through the constructive ownership rules of the Code, 10% or more of the voting power or value of Platinum Holdings. Except for matters where it is explicitly stated that we will not receive an opinion of counsel, the statements as to U.S. federal income tax law set forth below are the opinion of Dewey Ballantine LLP, our U.S. counsel, as to such tax laws (subject to the qualifications, assumptions and factual determinations set forth in such statements). The statements as to Bermuda tax law set forth below are the opinion of Conyers, Dill & Pearman, our Bermuda counsel, as to such tax laws (subject to the qualifications and assumptions set forth in such statements). The statements as to U.K. tax law set forth below are the opinion of Slaughter and May, our U.K. counsel, as to such tax laws (subject to the qualifications and assumptions set forth in such statements). The statements as to Irish tax law set forth below are the opinion of A. & L. Goodbody, our Irish counsel, as to such tax laws (subject to the qualifications and assumptions set forth in such statements). You are urged to consult your tax advisor as to the tax consequences of ownership and disposition of the offered securities. This discussion is limited to the tax consequences of ownership and disposition of common shares. Tax considerations applicable to other types of securities will be described in the related prospectus supplement.

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Taxation of the Company, Platinum US, Platinum UK, Platinum Bermuda and Platinum Ireland Bermuda

      Under current Bermuda law, there is no income tax, capital gains tax or withholding tax payable by us or Platinum Bermuda. Platinum Holdings and Platinum Bermuda have received from the Bermuda Minister of Finance a standard assurance under Bermuda’s Exempted Undertakings Tax Protection Act 1966, to the effect that in the event any legislation is enacted in Bermuda imposing any tax computed on profits or income, or computed on any capital asset, gain or appreciation, or any tax in the nature of estate duty or inheritance tax, then the imposition of any such tax shall not be applicable to Platinum Holdings, Platinum Bermuda, or any of their operations or the shares, debentures or other obligations of Platinum Holdings or Platinum Bermuda, until 2016. This assurance is subject to the proviso that it is not construed so as to prevent the application of any tax or duty to such persons as are ordinarily resident in Bermuda (Platinum Holdings and Platinum Bermuda are not currently so affected) or to prevent the application of any tax payable in accordance with the provisions of the Land Tax Act 1967 of Bermuda or otherwise payable in relation to the property leased to us or Platinum Bermuda.

United States Federal Income Taxation

      We have structured and operated Platinum Holdings, Platinum UK, Platinum Bermuda and Platinum Ireland in such a manner that they will not be considered to be conducting a trade or business within the U.S. for purposes of U.S. federal income taxation. Whether business is being conducted in the U.S. is an inherently factual determination depending on such matters as (i) the size and substance of the offices of our non-U.S. subsidiaries, (ii) whether employees of non-U.S. subsidiaries make binding decisions while physically present in the U.S., (iii) the number of employees permanently located in the offices of our non-U.S. subsidiaries, and the levels of their managerial importance and (iv) the situs of meetings of our board of directors and the boards of directors of our non-U.S. subsidiaries. Because of the factual nature of these matters and because definitive identification of activities which constitute being engaged in a trade or business in the U.S. is not provided by the Code or regulations or court decisions, counsel will not render an opinion regarding whether these entities are to be deemed to be conducting business in the U.S. The IRS might successfully contend that Platinum Holdings, Platinum UK, Platinum Bermuda and/or Platinum Ireland is engaged in a trade or business in the U.S. A foreign corporation deemed to be engaged in a U.S. trade or business is subject to U.S. federal income tax, as well as branch profits tax in certain circumstances, on its income which is treated as effectively connected with the conduct of that trade or business unless the corporation is entitled to relief under the permanent establishment provision of an applicable tax treaty, as discussed below. Such income tax, if imposed, would be based on effectively connected income computed in a manner generally analogous to that applied to the income of a domestic corporation, except that a foreign corporation is entitled to deductions and credits only if it files a U.S. income tax return. Under regulations, the foreign corporation would be entitled to deductions and credits for the taxable year only if the return for that year is timely filed under rules set forth therein. Penalties may be assessed for failure to file tax returns. Platinum Holdings and Platinum Bermuda have filed protective U.S. federal income tax returns. The federal tax rates currently are a maximum of 35% for a corporation’s effectively connected income and 30% for branch profits tax. The branch profits tax is imposed on net income after subtracting the regular corporate tax and making certain other adjustments.

      Under the income tax treaty between Bermuda and the United States, Platinum Bermuda is not subject to United States income tax on any net premium income found to be effectively connected with a U.S. trade or business unless that trade or business is conducted through a permanent establishment in the United States. It is unclear whether the Bermuda treaty is equally applicable to investment income. Because of the factual nature of, and the lack of definitive parameters for determining the existence of, a permanent establishment and the lack of clarity in the Bermuda treaty with respect to its applicability to investment income, counsel will not render an opinion with respect to whether Platinum Bermuda will have a permanent establishment in the U.S. or whether the Bermuda treaty protects investment income not attributable to a U.S. permanent

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      Under the income tax treaty between the United Kingdom and the U.S. (the “U.K. Treaty”), Platinum UK will not be subject to United States income tax on any income found to be effectively connected with a U.S. trade or business unless that trade or business is conducted through a permanent establishment in the U.S. Platinum UK will be entitled to the benefits of the U.K. Treaty if:

      Under the income tax treaty between Ireland and the United States (the “Irish Treaty”), Platinum Ireland is not subject to United States income tax on any income determined to be effectively connected with a U.S. trade or business unless that trade or business is conducted through a permanent establishment in the U.S. Platinum Ireland will generally be entitled to the benefits of the Irish treaty if at least 50 percent of the shares of Platinum Holdings, measured by both vote and value, are owned by U.S. citizens or residents. Because of the factual nature of, and the lack of definitive parameters for, determining the existence of a permanent establishment, counsel will not render an opinion with respect to whether Platinum Ireland will have a permanent establishment in the U.S.

      Foreign corporations not engaged in a trade or business in the U.S. are nonetheless subject to U.S. withholding tax at a rate of 30% of the gross amount of certain “fixed or determinable annual or periodical gains, profits and income” derived from sources within the U.S. (such as dividends and certain interest on investments), subject to reduction by applicable treaties. Dividends paid by Platinum Finance to Platinum Ireland will be subject to withholding at a rate of 5%, provided that Platinum Ireland is entitled to the benefits of the Irish Treaty as described above and certain other requirements are met. If Platinum Ireland is not entitled to the benefits of the Irish Treaty and/or certain other requirements are not met, dividends paid by Platinum Finance to Platinum Ireland will be subject to withholding at a rate of 30%.

      The U.S. also imposes an excise tax on insurance and reinsurance premiums paid to foreign insurers or reinsurers with respect to risks located in the U.S. the rate of tax applicable to premiums paid to Platinum Bermuda is 1% for reinsurance premiums. The excise tax does not apply to premiums paid to Platinum UK, provided that Platinum UK is entitled to the benefits of the UK Treaty and certain other requirements are met.

      Platinum Finance and Platinum US are U.S. corporations and are subject to taxation in the U.S. at regular corporate rates.

The United Kingdom

      Platinum UK is a U.K. resident company which will be subject to corporation tax in the United Kingdom on its worldwide profits. The current rate of U.K. taxation applicable to U.K. resident corporations is generally 30%. Currently, no U.K. withholding tax applies to dividends paid by Platinum UK.

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Ireland

      Under relevant case law and practice a company is resident in Ireland for tax purposes if its central management and control is, as a matter of fact, located in Ireland. It is assumed, for the purposes of the material under this heading, that Platinum Ireland is resident in Ireland for tax purposes.

      Platinum Ireland is subject to Irish corporate tax on its worldwide income. Dividends received by it from Platinum Finance and Platinum UK are subject to Irish corporate tax (at the current applicable rate of 25%) subject to any available relief under the double tax treaties Ireland has with the United States and the United Kingdom.

      Platinum Ireland will generally be entitled to the benefits of the Irish Treaty if at least 50% of the shares of Platinum Holdings, measured by both vote and value, are owned by US citizens or residents. Assuming that Platinum Ireland is entitled to the benefits of the Irish Treaty in respect of dividends from Platinum Finance, it would be entitled to a credit against Irish corporation tax on the dividends for US tax imposed on the profits out of which the dividends are declared. Alternatively, relief for US tax may be available under Irish domestic law.

      Assuming that Platinum Ireland is entitled to the benefits of the tax treaty between Ireland and the United Kingdom in respect of dividends received from Platinum UK it would be entitled to a credit against Irish corporation tax on the dividends for UK tax imposed on the profits out of which the dividends are declared.

      Platinum Ireland is subject to Irish corporate tax on any trading income at a rate of 12.5%.

      Platinum Ireland will be exempt from the Irish capital duty of 1% (on the value of share capital issued by it) because it is a unlimited liability company.

Taxation of Shareholders

      Currently, there is no Bermuda withholding tax on dividends paid by us or Platinum Bermuda.

United States Taxation of U.S. and Non-U.S. Shareholders

      General. The following discussion is the opinion of Dewey Ballantine LLP, our U.S. tax counsel, as to the material U.S. federal income tax consequences relating to the acquisition, ownership and disposition of common shares if you are a beneficial owner of common shares and you are:

      Dividends. Distributions with respect to your common shares will be treated as ordinary dividend income to the extent of the Company’s current or accumulated earnings and profits as determined for

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      Classification of Platinum Holdings, Platinum UK, Platinum Bermuda or Platinum Ireland as a Controlled Foreign Corporation. Each “United States shareholder” of a foreign corporation that is a “controlled foreign corporation” (“CFC”) for an uninterrupted period of 30 days or more during a taxable year, and who owns shares in the CFC directly or indirectly through foreign entities on the last day of the CFC’s taxable year must include in its gross income for U.S. federal income tax purposes its pro rata share of the CFC’s “subpart F income”, even if the subpart F income is not distributed. If Platinum Holdings, Platinum Bermuda, Platinum Ireland and/or Platinum UK is deemed to be a CFC, substantially all of Platinum Holdings’ income and that of each of Platinum Bermuda and Platinum Ireland will be subpart F income. Any U.S. corporation, citizen, resident or other U.S. person who owns, directly or indirectly through foreign persons, or is considered to own (by application of the rules of constructive ownership set forth in Code section 958(b), applying to family members, partnerships, estates, trusts or controlled corporations or holders of certain options, including for these purposes, holders of our equity security units) 10% or more of the total combined voting power of all classes of stock of the foreign corporation will be considered to be a “United States shareholder”. A foreign insurance company such as Platinum UK or Platinum Bermuda is treated as a CFC (other than for purposes of related person insurance income, as described below) only if its “United States shareholders” collectively own more than 25% of the total combined voting power or total value of the corporation’s stock. Because of the limitations on concentration of voting power of our common shares, the dispersion of our share ownership among holders other than St. Paul and its subsidiaries, and the restrictions on transfer, issuance or repurchase of common shares, you should not be subject to treatment as a United States shareholder of a CFC. However, these prophylactic provisions have not been tested in court and it is possible that they could be challenged by the Internal Revenue Service and found to be ineffective in preventing CFC status from arising. Because our Bye-laws provide that no single shareholder (including St. Paul) is permitted to hold as much as 10% of the total combined voting power of Platinum Holdings, shareholders of Platinum Holdings should not be viewed as United States shareholders of a CFC for purposes of these rules. Again, there can be no assurance that these ownership limitations will be effective. Assuming they are effective, however, neither the indirect foreign tax credit nor the intercompany dividends received deduction attributable to U.S. source income will be available to U.S. corporate holders of the common shares who, absent such provision, would qualify therefor.

      RPII Companies. Different definitions of “United States shareholder” and “controlled foreign corporation” are applicable in the case of a foreign corporation which earns “related person insurance income” (“RPII”). RPII is defined in Code section 953(c)(2) as any “insurance income” attributable to policies of insurance or reinsurance with respect to which the person (directly or indirectly) insured is a “United States shareholder” or a “related person” to such a shareholder. In general, and subject to certain limitations, “insurance income” is income (including premium and investment income) attributable to the issuing of any insurance or reinsurance contract in connection with risks located in a country other than the country under the laws of which the controlled foreign corporation is created or organized and which would be taxed under the portions of the Code relating to insurance companies if the income were the income of a domestic insurance company.

      The term “related person” for this purpose means someone who controls or is controlled by the United States shareholder or someone who is controlled by the same person or persons which control the United States shareholder. “Control” is measured by either more than 50% in value or more than 50% in voting power

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RPII Exceptions. The special RPII rules do not apply if:

      Platinum UK and Platinum Bermuda have not and do not intend to make either of the elections described above. Additionally, as subsidiaries of St. Paul and RenaissanceRe may be reinsured by Platinum UK and/or Platinum Bermuda, persons related to insureds may indirectly own more than 20% of the value of the stock of Platinum UK and Platinum Bermuda. Thus, only the second exception may be available.

      Where none of these exceptions applies, each U.S. person who owns directly or indirectly shares in Platinum Holdings (and therefore, indirectly in Platinum UK and Platinum Bermuda) at the end of any taxable year, will be required to include in its gross income for United States federal income tax purposes its share of RPII of Platinum UK and/or Platinum Bermuda for the entire taxable year. This inclusion will be determined as if such RPII were distributed proportionately only to such United States shareholders holding common shares at the end of the taxable year. The inclusion will be limited to the current-year earnings and profits of Platinum UK or Platinum Bermuda, as applicable, reduced by the shareholder’s pro rata share, if any, of certain prior-year deficits in earnings and profits.

      Computation of RPII. In order to determine how much RPII each of Platinum UK and Platinum Bermuda has earned in each taxable year, we will obtain and rely upon information from Platinum UK’s and Platinum Bermuda’s insureds and reinsureds to determine whether any of the insureds, reinsureds or other persons related to such insureds or reinsureds own our shares and are U.S. persons. Each year, each of Platinum UK and Platinum Bermuda will send a letter after the most recent taxable year to each person who was a policyholder to represent whether it was a United States shareholder of the Company or related to a United States shareholder during the year. For any taxable year in which Platinum UK’s or Platinum Bermuda’s gross RPII is 20% or more of its gross insurance income for the year, we may also seek information from our shareholders as to whether direct or indirect owners of our shares at the end of the year are U.S. persons so that the RPII may be determined and apportioned among such persons. To the extent we are unable to determine whether a direct or indirect owner of shares is a U.S. person, we may assume that such owner is not a U.S. person, thereby increasing the per share RPII amount for all United States shareholders.

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      Apportionment of RPII to United States Shareholders. If Platinum UK’s or Platinum Bermuda’s RPII for any future taxable year is 20% or more of its gross insurance income, every U.S. person directly or indirectly owning common shares on the last day of that year will be required to include in gross income its share of Platinum UK’s or Platinum Bermuda’s RPII for such year, whether or not distributed. A U.S. person owning common shares during our taxable year but not on the last day of the taxable year for which Platinum Bermuda and/or Platinum UK is a controlled foreign corporation within the meaning of the RPII provisions of the Code, which would normally be December 31, is not required to include in gross income any part of Platinum UK’s or Platinum Bermuda’s RPII. Correspondingly, a U.S. person directly or indirectly owning common shares on the last day of the taxable year in which Platinum UK or Platinum Bermuda is a controlled foreign corporation for purposes of these provisions is required to include in its income its pro rata share of the RPII for the entire year, even though it did not own the common shares for the entire year.

      Information Reporting. Each U.S. person who is a direct or indirect shareholder of Platinum Holdings on the last day of our taxable year must attach to the income tax or information return it would normally file for the period which includes that date a Form 5471 if Platinum UK or Platinum Bermuda is a CFC for RPII purposes for any continuous thirty-day period during its taxable year, whether or not any net RPII income is required to be reported. Platinum UK or Platinum Bermuda, as the case may be, will not be considered to be a CFC for this purpose and, therefore, Form 5471 will not be required, for any taxable year in which Platinum UK’s or Platinum Bermuda’s gross RPII constitutes less than 20% of its gross insurance income. For any year in which Platinum UK’s or Platinum Bermuda’s gross RPII constitutes 20% or more of its gross insurance income, we intend to provide Form 5471 to our direct or indirect United States shareholders for attachment to the returns of such shareholders. The amounts of the RPII inclusions may be subject to adjustment based upon subsequent IRS examination. A tax-exempt organization will be required to attach Form 5471 to its information return in the circumstances described above. Failure to file Form 5471 may result in penalties. In addition, U.S. persons who at any time acquire 10% or more of our shares will have an independent obligation to file Form 5471.

      Tax-Exempt Shareholders. Tax-exempt entities will be required to treat certain subpart F insurance income, including RPII, that is includible in income by the tax-exempt entity as unrelated business taxable income.

      Distributions; Basis; Exclusion of Distributions from Gross Income. A United States shareholder’s tax basis in its common shares will be increased by the amount of any RPII that the shareholder includes in income. The shareholder may exclude from income the amount of any distribution by us to the extent of the RPII included in income for the year in which the distribution was paid or for any prior year. The United States shareholder’s tax basis in its common shares will be reduced by the amount of such distributions that are excluded from income. While, in certain circumstances, a United States shareholder may be able to exclude from income distributions with respect to RPII that a prior shareholder included in income, that exclusion will not generally be available to holders who purchase common shares in this offering or in the public trading markets and are therefore unable to identify the previous shareholder and demonstrate that such shareholder had previously included the RPII in income.

      Dispositions of Common Shares. Subject to the discussion below relating to the potential application of Code section 1248 or the passive foreign investment company rules, you will recognize a gain or loss for United States federal income tax purposes upon the sale or exchange of any common shares equal to the difference between the amount realized upon such sale or exchange and your basis in the common shares. If your holding period for these common shares is more than one year, any gain will be subject to tax at a current maximum marginal tax rate of 15% for individuals and 35% for corporations.

      Code section 1248 provides that if a U.S. person disposes of stock in a foreign corporation and such person owned directly, indirectly through certain foreign entities or constructively 10% or more of the voting shares of the corporation at any time during the five-year period ending on the date of disposition when the corporation was a CFC, any gain from the sale or exchange of the shares may be treated as ordinary income to the extent of the CFC’s earnings and profits during the period that the shareholder held the shares (with certain adjustments). A 10% United States shareholder may in certain circumstances be required to report a

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      Foreign Tax Credit. If U.S. persons own a majority of the Company’s shares, only a portion of the current income inclusions under the CFC, RPII and passive foreign investment company rules, if any, and of dividends paid by us (including any gain from the sale of common shares that is treated as a dividend under section 1248 of the Code) will be treated as foreign source income for purposes of computing a shareholder’s U.S. foreign tax credit limitation.

      Uncertainty as to Application of RPII. Regulations interpreting the RPII provisions of the Code exist only in proposed form. It is not certain whether these regulations will be adopted in their proposed form or what changes might ultimately be made or whether any such changes, as well as any interpretation or application of the RPII rules by the IRS, the courts or otherwise, might have retroactive effect. Accordingly, the meaning of the RPII provisions and their application to Platinum UK and Platinum Bermuda is uncertain. These provisions include the grant of authority to the U.S. Treasury to prescribe “such regulations as may be necessary to carry out the purposes of this subsection, including . . . regulations preventing the avoidance of this subsection through cross insurance arrangements or otherwise”. In addition, there can be no assurance that the IRS will not challenge any determinations by Platinum UK or Platinum Bermuda as to the amount, if any, of RPII that should be includible in your income or that the amounts of the RPII inclusions will not be subject to adjustment based upon subsequent IRS examination. Each U.S. person considering an investment in common shares should consult its tax advisor as to the effects of these uncertainties.

      Passive Foreign Investment Companies. Sections 1291 through 1298 of the Code contain special rules applicable to foreign corporations that are “passive foreign investment companies” (“PFICs”). In general, a foreign corporation will be a PFIC during a given year if:

      If we were to be characterized as a PFIC during a given year, our United States shareholders would be subject to a penalty tax at the time of their sale at a gain of, or receipt of an “excess distribution” with respect to, their common shares, unless such shareholders elected to be taxed on their pro rata share of our earnings whether or not such earnings were distributed or elected to be taxed on the investment in common shares on a mark-to-market basis. In general, a shareholder receives an “excess distribution” if the amount of the distribution is more than 125% of the average distribution with respect to the stock during the three preceding taxable years (or shorter period during which the taxpayer held the stock). In general, the penalty tax is equivalent to an interest charge on taxes that are deemed due during the period the United States shareholder owned the shares, computed by assuming that the excess distribution or gain (in the case of a sale) with respect to the shares was taxed in equal portions at the highest applicable tax rate on ordinary income

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      For the above purposes, passive income is defined to include income of the kind which would be foreign personal holding company income under Code section 954(c), and generally includes interest, dividends, annuities and other investment income. The PFIC statutory provisions, however, contain an express exception for income “derived in the active conduct of an insurance business by a corporation which is predominantly engaged in an insurance business ...”.

      This exception is intended to ensure that income derived by a bona fide insurance company is not treated as passive income, except to the extent such income is attributable to financial reserves in excess of the reasonable needs of the insurance business. We expect, for purposes of the PFIC rules, that each of Platinum UK and Platinum Bermuda will be predominantly engaged in an insurance business and is unlikely to have financial reserves in excess of the reasonable needs of its insurance business. The PFIC statutory provisions contain a look-through rule stating that, for purposes of determining whether a foreign corporation is a PFIC, such foreign corporation shall be treated as if it received “directly its proportionate share of the income ...” and as if it “held its proportionate share of the assets ...” of any other corporation in which it owns at least 25% by value of the stock. While no explicit guidance is provided by the statutory language, under this look-through rule we should be deemed to own the assets and to have received the income of our insurance subsidiaries directly for purposes of determining whether we qualify for the insurance exception. This interpretation of the look-through rule is consistent with the legislative intention generally to exclude bona fide insurance companies from the application of PFIC provisions; there can, of course, be no assurance as to what positions the IRS or a court might take in the future. Each U.S. person considering an investment in common shares should consult its tax advisor as to the effects of the PFIC rules.

      Other. Except as discussed below with respect to backup withholding, dividends paid by us will not be subject to U.S. withholding tax.

      Transfer Reporting Requirements. A U.S. person (including a tax exempt entity) that transfers our common shares to a non-U.S. person may be required to file a Form 926 or similar form with the IRS if the cost of such purchases, including the cost of certain related purchases and purchases by related persons, exceeds $100,000. In the event such person fails to file any such required form, such person could be required to pay a penalty equal to 10% of the gross amount paid for such common shares (subject to a maximum penalty of $100,000, except in cases involving intentional disregard). U.S. persons should consult their tax advisors with respect to this or any other reporting requirement which may apply with respect to their acquisition of our common shares.

      Subject to certain exceptions, non-U.S. persons will be subject to United States federal income tax on dividend distributions with respect to, and gain realized from the sale or exchange of, common shares only if such dividends or gains are effectively connected with the conduct of a trade or business within the U.S. Nonresident alien individuals will not be subject to U.S. estate tax with respect to our common shares.

      Information reporting to the IRS by paying agents and custodians located in the United States will be required with respect to payments of dividends on the common shares to U.S. persons. Thus, you may be subject to backup withholding with respect to dividends paid by such persons, unless you:

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      Backup withholding is not an additional tax and may be credited against your regular federal income tax liability.

Proposed U.S. Tax Legislation

      Congress is currently considering a revision of certain aspects of the U.S. tax system as applicable to non-U.S. corporations and their shareholders. At the present time, the version of the bill that Congress is considering will not negatively impact the Company or its shareholders. There can be no assurance, however, that the bill that is ultimately passed by Congress will not adversely affect the Company or its shareholders. Investors should consult their tax advisor to determine the impact of any changes in U.S. federal income tax law on the Company or on your investment in our common shares.

United Kingdom Taxation

      The following discussion applies only to U.K. resident individuals and U.K. resident companies who beneficially own shares in Platinum Holdings and who hold those shares as capital assets and not as dealers.

      Such individuals will be liable to tax on dividends received, at a rate of 10% for those shareholders who are subject to tax only at the basic rate, and 32.5% for those shareholders who are liable to tax at the higher rate of tax. Individual shareholders who while resident in the U.K. are non-U.K. domiciled will be chargeable to tax in respect of dividends only if and to the extent that the dividends are remitted to or enjoyed in the United Kingdom in any way.

      Individual shareholders are potentially liable to capital gains tax in respect of chargeable gains arising on any disposal of their shares. Once again, resident shareholders who are non-U.K. domiciled will be chargeable to capital gains tax on a disposal of their shares only as regards remittances made to the United Kingdom of the proceeds.

      For U.K. inheritance tax purposes, the shares of Platinum Holdings will rank as non-U.K. assets which may have a bearing on the imposition of inheritance tax in relation to gifts or the passing of the shares on death, particularly where the donor or deceased was non-U.K. domiciled.

      U.K. companies will be liable to corporation tax at the ordinary rate in relation to dividends received on the shares and gains arising on the disposal of the shares.

      Were a U.K. company ever to hold shares that carried the entitlement (aggregated with shares held by certain connected persons) to at least 25% of the profits of Platinum, the U.K.’s Controlled Foreign Companies provisions could be material, with the result that in certain circumstances underlying profits of Platinum and its subsidiaries might be taxed in the hands of the U.K. shareholder.

      Prospective investors should consult their own tax advisors concerning any federal, state, local and non-U.S. Tax Consequences of Ownership and Disposition of the Common Shares which are particular to them.

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PLAN OF DISTRIBUTION

      We and/or the selling shareholders may sell offered securities in any one or more of the following ways from time to time:

      The prospectus supplement with respect to the offered securities will set forth the terms of the offering of the offered securities, including the name or names of any underwriters, dealers or agents; the purchase price of the offered securities and the proceeds to us and/or the selling shareholders from such sale; any underwriting discounts and commissions or agency fees and other items constituting underwriters’ or agents’ compensation; any public offering price and any discounts or concessions allowed or reallowed or paid to dealers and any securities exchange on which such offered securities may be listed. Any public offering price, discounts or concessions allowed or reallowed or paid to dealers may be changed from time to time.

      The selling shareholders may offer their common shares in one or more offerings pursuant to one or more prospectus supplements, and each such prospectus supplement will set forth the terms of the relevant offering as described above. To the extent the common shares offered pursuant to a prospectus supplement remain unsold, the selling shareholder may offer those common shares on different terms pursuant to another prospectus supplement, provided that no selling shareholder may offer or sell more common shares in the aggregate than are indicated in the table set forth under the caption “Selling Shareholders” pursuant to any such prospectus supplements.

      The distribution of the offered securities may be effected from time to time in one or more transactions at a fixed price or prices, which may be changed, at market prices prevailing at the time of sale, at prices related to such prevailing market prices or at negotiated prices.

      Offers to purchase offered securities may be solicited by agents designated by us from time to time. Any such agent involved in the offer or sale of the offered securities in respect of which this prospectus is delivered will be named, and any commissions payable by us and/or the selling shareholders to such agent will be set forth, in the applicable prospectus supplement. Unless otherwise indicated in such prospectus supplement, any such agent will be acting on a reasonable best efforts basis for the period of its appointment. Any such agent may be deemed to be an underwriter, as that term is defined in the Securities Act, of the offered securities so offered and sold.

      If offered securities are sold by means of an underwritten offering, we and/or the selling shareholders will execute an underwriting agreement with an underwriter or underwriters, and the names of the specific managing underwriter or underwriters, as well as any other underwriters, and the terms of the transaction, including commissions, discounts and any other compensation of the underwriters and dealers, if any, will be set forth in the prospectus supplement which will be used by the underwriters to make resales of the offered securities. If underwriters are utilized in the sale of the offered securities, the offered securities will be acquired by the underwriters for their own account and may be resold from time to time in one or more transactions, including negotiated transactions, at fixed public offering prices or at varying prices determined by the underwriters at the time of sale.

      Our offered securities may be offered to the public either through underwriting syndicates represented by managing underwriters or directly by the managing underwriters. If any underwriter or underwriters are utilized in the sale of the offered securities, unless otherwise indicated in the prospectus supplement, the underwriting agreement will provide that the obligations of the underwriters are subject to certain conditions precedent and that the underwriters with respect to a sale of offered securities will be obligated to purchase all such offered securities of a series if any are purchased. We, and/or the selling shareholders may grant to the underwriters options to purchase additional offered securities, to cover over-allotments, if any, at the public

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      If a dealer is utilized in the sales of offered securities in respect of which this prospectus is delivered, we and/or the selling shareholders will sell such offered securities to the dealer as principal. The dealer may then resell such offered securities to the public at varying prices to be determined by such dealer at the time of resale. Any such dealer may be deemed to be an underwriter, as such term is defined in the Securities Act, of the offered securities so offered and sold. The name of the dealer and the terms of the transaction will be set forth in the related prospectus supplement.

      Offers to purchase offered securities may be solicited directly by us and/or the selling shareholders and the sale thereof may be made by us and/or the selling shareholders directly to institutional investors or others, who may be deemed to be underwriters within the meaning of the Securities Act with respect to any resale thereof. The terms of any such sales will be described in the related prospectus supplement.

      We may enter into derivative or other hedging transactions with financial institutions. These financial institutions may in turn engage in sales of common shares to hedge their position, deliver this prospectus in connection with some or all of those sales and use the shares covered by this prospectus to close out any short position created in connection with those sales. We may also sell our common shares short using this prospectus and deliver common shares covered by this prospectus to close out such short positions, or loan or pledge common shares to financial institutions that in turn may sell the common shares using this prospectus. We may pledge or grant a security interest in some or all of the common shares covered by this prospectus to support a derivative or hedging position or other obligation and, if we default in the performance of our obligations, the pledgees or secured parties may offer and sell the common shares from time to time pursuant to this prospectus.

      Offered securities may also be offered and sold, if so indicated in the applicable prospectus supplement, in connection with a remarketing upon their purchase, in accordance with a redemption or repayment pursuant to their terms, or otherwise, by one or more firms (“remarketing firms”), acting as principals for their own accounts or as agents for us. Any remarketing firm will be identified and the terms of its agreements, if any, with us and its compensation will be described in the applicable prospectus supplement. Remarketing firms may be deemed to be underwriters, as such term is defined in the Securities Act, in connection with the offered securities remarketed thereby.

      Agents, underwriters, dealers and remarketing firms may be entitled under relevant agreements entered into with us to indemnification by us against certain civil liabilities, including liabilities under the Securities Act that may arise from any untrue statement or alleged untrue statement of a material fact or any omission or alleged omission to state a material fact in this prospectus, any supplement or amendment hereto, or in the registration statement of which this prospectus forms a part, or to contribution with respect to payments which the agents, underwriters, dealers or remarketing firms may be required to make.

      If so indicated in the prospectus supplement, we will authorize underwriters or other persons acting as our agents to solicit offers by certain institutions to purchase offered securities from us pursuant to contracts providing for payments and delivery on a future date. Institutions with which such contracts may be made include commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and others, but in all cases such institutions must be approved by us. The obligations of any purchaser under any such contract will be subject to the condition that the purchase of the offered securities shall not at the time of delivery be prohibited under the laws of the jurisdiction to which such purchaser is subject. The underwriters and such other agents will not have any responsibility in respect of the validity or performance of such contracts.

      Disclosure in the prospectus supplement of our use of delayed delivery contracts will include the commission that underwriters and agents soliciting purchases of the securities under delayed contracts will be entitled to receive in addition to the date when we will demand payment and delivery of the securities under

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      Each series of offered securities will be a new issue and, other than the common shares which are listed on the New York Stock Exchange, will have no established trading market. We may elect to list any series of offered securities on an exchange, and in the case of the common shares, on any additional exchange, but, unless otherwise specified in the applicable prospectus supplement, we shall not be obligated to do so. No assurance can be given as to the liquidity of the trading market for any of the offered securities.

      Underwriters, dealers, agents and remarketing firms, as well as their respective affiliates, may be customers of, engage in transactions with, or perform services for, us and our subsidiaries in the ordinary course of business.

WHERE YOU CAN FIND MORE INFORMATION

General

      We have filed with the Securities and Exchange Commission, a registration statement on Form S-3 under the Securities Act with respect to the common shares, preferred shares, depositary shares, debt securities, warrants, purchase contracts and purchase units offered by this prospectus. This prospectus, filed as part of the registration statement, does not contain all of the information set forth in the registration statement and its exhibits and schedules, portions of which have been omitted as permitted by the rules and regulations of the SEC. For further information about us and the securities, we refer you to the registration statement and to its exhibits and schedules. Statements in this prospectus about the contents of any contract, agreement or other document are not necessarily complete and, in each instance, we refer you to the copy of such contract, agreement or document filed as an exhibit to the registration statement, with each such statement being qualified in all respects by reference to the document to which it refers. Anyone may inspect the registration statement and its exhibits and schedules without charge at the public reference facilities the SEC maintains at 450 Fifth Street, N.W., Washington, D.C. 20549. You may obtain copies of all or any part of these materials from the SEC upon the payment of certain fees prescribed by the SEC. You may obtain further information about the operation of the SEC’s Public Reference Room by calling the SEC at 1-800-SEC-0330. You may also inspect these reports and other information without charge at a web site maintained by the SEC. The address of this site is http://www.sec.gov.

      We are subject to the informational requirements of the Exchange Act. Accordingly, we file annual, quarterly and current reports, proxy statements and other information with the SEC. You may inspect and copy these reports, proxy statements and other information at the public reference facilities maintained by the SEC at the address noted above. You also may obtain copies of this material from the Public Reference Room of the SEC as described above, or inspect them without charge at the SEC’s web site or at our web site, the address of which is http://www.platinumre.com. We also furnish our shareholders with annual reports containing consolidated financial statements audited by an independent accounting firm. Our web site is not incorporated into or otherwise a part of this prospectus.

INCORPORATION OF CERTAIN DOCUMENTS BY REFERENCE

      We file annual, quarterly and current reports, proxy statements and other information with the SEC. The SEC allows us to “incorporate by reference” the information we file with it, which means that we can disclose important information to you by referring to those documents. The information incorporated by reference is an important part of this prospectus. Any statement contained in a document which is incorporated by reference in this prospectus is automatically updated and superseded if information contained in this prospectus, or information that we later file with the Commission, modifies or replaces this information. All documents we file pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act, after the initial filing of this

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      To receive a free copy of any of the documents incorporated by reference in this prospectus (other than exhibits to the registration statement of which this prospectus is a part), call or write us at the following address: Platinum Underwriters Holdings, Ltd., The Belvedere Building, 69 Pitts Bay Road, Pembroke, Bermuda HM 08, Bermuda, (441) 295-7195.

LEGAL MATTERS

      Certain matters as to U.S. law in connection with this offering will be passed upon for us by Dewey Ballantine LLP. Certain matters as to Bermuda law in connection with this offering will be passed upon for us by Conyers Dill & Pearman, Hamilton, Bermuda. Certain matters as to United Kingdom law will be passed upon for us by Slaughter and May. Certain matters as to Irish law will be passed upon for us by A. & L. Goodbody. Additional legal matters may be passed on for us, any underwriters, dealers or agents by counsel which we will name in the applicable prospectus supplement.

EXPERTS

      The consolidated balance sheets of Platinum Underwriters Holdings, Ltd. as of December 31, 2003 and 2002 and the related consolidated statements of income and comprehensive income, shareholders’ equity and cash flows for the year ended December 31, 2003 and the period from April 19, 2002 (date of inception) to December 31, 2002, and all related financial statement schedules, incorporated in this prospectus by reference to the Annual Report on Form 10-K for the year ended December 31, 2003 have been audited by KPMG LLP, independent auditors, as set forth in their reports appearing therein. The consolidated financial statements and financial statement schedules referred to above are included in reliance upon such reports of KPMG LLP, given upon the authority of such firm as experts in accounting and auditing.

      The combined statements of underwriting results and identifiable underwriting cash flows of The St. Paul Companies, Inc. Reinsurance Underwriting Segment (Predecessor) for the period from January 1, 2002 through November 1, 2002 and the year ended December 31, 2001 incorporated in this prospectus by reference to the Annual Report on Form 10-K for the year ended December 31, 2003 have been audited by KPMG LLP, independent auditors, as set forth in their report appearing therein. The combined statements referred to above are included in reliance upon such report of KPMG LLP, given upon the authority of such firm as experts in accounting and auditing. The audit report covering Predecessor’s combined statements contains an explanatory paragraph that states that the combined statements are not intended to be a complete presentation of Predecessor’s or St. Paul’s financial position, results of operations, or cash flows.

ENFORCEMENT OF CIVIL LIABILITIES UNDER

      Platinum Holdings is a Bermuda company, and certain of its officers and directors are or will be residents of various jurisdictions outside the United States. A substantial portion of the assets of Platinum Holdings (in particular the assets of Platinum Bermuda, which is also a Bermuda company) and of such officers and directors, at any one time, are or may be located in jurisdictions outside the United States. Therefore, it could be difficult for investors to effect service of process within the United States on Platinum Holdings or any of its

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      We will deliver a copy of this prospectus to the Registrar of Companies in Bermuda for filing pursuant to the Companies Act. However, the Bermuda Monetary Authority and Registrar of Companies in Bermuda accept no responsibility for the financial soundness of any proposal or for the correctness of any of the statements made or opinions expressed in this prospectus.

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