1. Name and Address of Reporting Person Monahan, William T. 1500 County Road B2 West Suite 400 St. Paul, MN 55113-3105 USA 2. Issuer Name and Ticker or Trading Symbol Pentair, Inc. (PNR) 3. IRS or Social Security Number of Reporting Person (Voluntary) 4. Statement for Month/Day/Year 03/12/2003 5. If Amendment, Date of Original (Month/Day/Year) 6. Relationship of Reporting Person(s) to Issuer (Check all applicable) (X) Director ( ) 10% Owner ( ) Officer (give title below) ( ) Other (specify below) 7. Individual or Joint/Group Filing (Check Applicable Line) (X) Form filed by One Reporting Person ( ) Form filed by More than One Reporting Person TABLE I -- Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned +------------------------------+----------+----------+---------+--------------------------+--------------+-----------+------------+ |1. Title of Security |2. Trans- |2A.Execu- |3. Trans-|4. Securities Acquired (A)|5. Amount of |6. Owner- |7. Nature | | | action | action | action| or Disposed of (D) |Securities | ship | of In- | | | Date | Date | Code | |Beneficially | Form: | direct | | | | | | |Owned | Direct | Bene- | | | (Month/ | (Month/ | | |Following | (D) or | ficial | | | Day/ | Day/ +-----+---+-----------+---+----------+Reported | Indirect| Owner- | | | Year) | Year) |Code |V |Amount |A/D|Price |Transaction(s)| (I) | ship | +------------------------------+----------+----------+-----+---+-----------+---+----------+--------------+-----------+------------+ Common Stock 500 D TABLE II -- Derivative Securities Acquired, Disposed of, or Beneficially Owned +----------+--------+-------+-------+---------+-----------+---------------------+----------------+----------+-------+-------+------+ |1. |2. |3. |3A. |4. |5. |6. |7. |8. |9. |10. |11. | | | | | | | | | | |Number |Owner- | | | | | | | | | | | |of |ship | | | | | | | | | | | |Deriv- |Form of| | | | | | | | | |Title and Amount| |ative |Deriv- | | | | | | | | | |of Underlying | |Secur- |ative |Nature| | |Conver- |Trans- |Execu- | |Number of | |Securities | |ities |Secur- |of | | |sion or |action |tion | |Derivative |Date Exercisable +-------+--------+ |Benefi-|ity: |In- | | |Exercise|Date |Date | |Securities |and Expiration Date | |Amount | |cially |Direct |direct| | |Price of| | |Transac- |Acquired(A)|(Month/Day/Year) | |or | |Owned |(D) or |Bene- | |Title of |Deriv- |(Month/|(Month/|tion Code|Disposed(D)+----------+----------+ |Number |Price of | |In- |ficial| |Derivative|ative | Day/ | Day/ +------+--+-----+-----+Date Exer-|Expira- | |of |Derivative| |direct |Owner-| |Security |Security|Year) |Year) |Code |V |(A) |(D) |cisable |tion Date |Title |Shares |Security | |(I) |ship | +----------+--------+-------+-------+------+--+-----+-----+----------+----------+-------+--------+----------+-------+-------+------+ Phantom 1 03/12/2 A77.83 Common 77.833 $34.5292 2562.84 I By Plan Stock Units 003 3 Stock Agent - Deferred Compensatio n Explanation of Responses: SIGNATURE OF REPORTING PERSON /s/ Louis L. Ainsworth, Attorney-in-Fact ______________________________ William T. Monahan DATE 03/13/2003 Represents phantom stock units credited under a deferred compensation plan for non-employee directors over which the reporting person has no current dispositive or voting power. Settlement of phantom stock units will be in Pentair common stock in accordance with reporting person's irrevocable election. Shares acquired under this Plan are purchased over a three-day trading period. The price shown is the average purchase price over the trading period.