Some of the market’s hottest stocks are grabbing headlines for all the right reasons. These three stocks have been fueled by strong growth, big artificial intelligence (AI) bets, and bold future potential. But beneath the excitement, valuations are now soaring. The question for investors now is, should you stay invested, or is it time to sell?

Overvalued Stock #1: Tesla (TSLA)

There are very few stocks that grab investors’ attention like Tesla (TSLA). From dominating headlines with its electric vehicles (EVs) to a potential powerhouse in AI and robotics, Tesla’s story is evolving fast. With expectations now sky-high, concerns are rising that the stock may be getting ahead of its fundamentals.

Tesla stock is down 11% so far this year but up 67% over the last 52 weeks.

Tesla’s core automotive business is struggling, with revenue down 11% year-over-year (YoY) to $17.7 billion in the fourth quarter and 10% to $69 billion for the full year. Even double-digit growth in the energy generation, storage, and services areas couldn't offset the decline in its core operations. Nonetheless, CEO Elon Musk cannot stop pulling all the focus on Tesla’s future rather than the present. The company is investing heavily in self-driving technology, robotics, particularly its humanoid robot Optimus, and AI-powered infrastructure and energy solutions. Musk identified them as key pillars of the company's long-term strategy. He believes that autonomous driving and robotics could reshape entire industries. 

While adjusted earnings declined 28% YoY in 2025, analysts expect double-digit growth over the next two years. Tesla's long-term goal is undeniably enticing, but its valuation raises plenty of questions. Trading at 189 times forward earnings, TSLA stock seems overpriced for an expected 24% growth in earnings for 2026. Investors are betting on widespread adoption of autonomous vehicles, successful commercialization of robotics, and Tesla becoming a leader in physical AI. However, these opportunities are still in early stages and may take a decade or more to materialize.

Should Investors Sell TSLA Stock Now?

I believe long-term investors who have trust in Tesla’s AI-driven future and have the patience to see Musk’s vision unfold may want to hold on to the stock. 

Overall, Wall Street remains cautiously optimistic as well, rating TSLA stock a “Hold.” Out of the 43 analysts covering the stock, 15 rate it a “Strong Buy,” two recommend a “Moderate Buy,” 17 rate it a “Hold,” and nine recommend a “Strong Sell.” The stock is trading 3.2% below its average analyst target price of $408.42. The high price estimate of $600 implies that the stock can rise by 52% in the next 12 months.

Overvalued Stock #2: Palantir Technologies (PLTR)

Palantir Technologies' (PLTR) stock has been on a remarkable run over the past month, fueled largely by rising geopolitical tensions, particularly the escalating U.S.–Iran war, which has pushed investors toward defense-focused and mission-critical technology companies.     

While the stock is down 12% so far this year, it has surged around 17% just over the last month. But with valuation concerns rising, the question is if this rally is sustainable.

Palantir’s AI-powered platforms, including Gotham, Foundry, and AIP, are designed to process vast amounts of data and deliver real-time insights, making them highly valuable in military and strategic environments. As defense agencies prioritize faster decision-making, demand for Palantir’s software has increased. Palantir’s government business remains its backbone. In 2025, its U.S. government revenue jumped 66% YoY to $570 million, helping drive total annual revenue up 56% to $4.4 billion.

The company is also strengthening its strategic footprint through high-profile partnerships with GE Aerospace (GE) and the U.S. Navy. Looking ahead, management is projecting continued momentum, with revenue rising 61% in 2026 to around $7.19 billion. 

Palantir’s commercial business is also now emerging as a powerful growth driver. Notably, U.S. commercial revenue surged 137% YoY in the fourth quarter and more than doubled for the full year. Both government contracts and commercial AI could support sustained expansion in the coming years. Analysts estimate Palantir’s 2026 earnings to increase by 76.2%, followed by a 41.2% increase in 2027.  Despite the impressive growth, Palantir’s valuation remains high at a forward price-to-earnings multiple of around 115x, a level that suggests high expectations are already priced in.

Should Investors Sell PLTR Stock Now?

For long-term investors who believe in the growing role of AI in defense and enterprise decision-making, Palantir’s positioning remains compelling. If global instability continues and AI demand accelerates, Palantir could justify its lofty valuation. 

Overall, Wall Street rates PLTR stock as a “Moderate Buy.” Of the 26 analysts covering the stock, 15 rate it a “Strong Buy,” eight rate it a “Hold,” one says it is a “Moderate Sell,” and two say it is a “Strong Sell.” Its average target price of $200.41 suggests PLTR stock could climb by 29% from current levels. Plus, its high price estimate of $260 suggests an upside potential of 68% over the next 12 months. 

Overvalued Stock #3: Arm Holdings (ARM)

Arm Holdings (ARM) has also been riding the AI wave. It creates energy-efficient processor designs (CPUs) that other companies like Apple (AAPL), Qualcomm (QCOM), and Nvidia (NVDA) use to build chips for smartphones, laptops, data centers, and AI systems.

ARM stock is up 16% so far this year, outperforming the S&P 500 Index ($SPX) dip of 2%.

In the third quarter of fiscal 2026, Arm’s revenue grew 26% YoY to $1.24 billion, marking its fourth consecutive quarter above the $1 billion mark. Royalty revenue surged 27% to $737 million, driven by higher chip volumes and growing adoption across AI and data center applications. Licensing revenue also rose 25% YoY to $505 million as some major tech players such as Alphabet (GOOG) (GOOGL), Nvidia, and Amazon (AMZN) signed high-value agreements for next-generation architectures. Adjusted earnings grew 10.2% to $0.43 per share, even as the company continued ramping up investments in research and development.

The industry shift toward “agent-based AI,” where systems operate continuously and require highly efficient CPUs, is benefitting Arm Holdings. The company’s CPUs, which offer strong performance per watt, are becoming an increasingly critical factor in large-scale AI deployments. Arm’s financial strength is backed by a growing base of long-duration licensing agreements and rising royalty rates.

Despite these strong fundamentals, valuation is a challenge now. The stock is trading at 56 times forward 2027 earnings, which are expected to increase by 21%. With high expectations already baked into the stock, any slowdown in AI adoption, licensing activity, or hyperscaler demand could weigh on ARM stock.

Should Investors Sell ARM Stock Now?

With real growth across multiple segments and a strong position in the rapidly expanding AI market, I believe Arm presents a compelling buy-and-hold stock for long-term investors.

Overall, Wall Street rates ARM stock as a “Moderate Buy.” Of the 31 analysts covering the stock, 20 rate it a “Strong Buy,” one says it is a “Moderate Buy,” nine rate it a “Hold,” and one says it is a “Strong Sell.” Its average target price of $153.31 suggests ARM stock could climb by 21% from current levels. Plus, its high price estimate of $210 suggests an upside potential of 65% over the next 12 months. 

More news from Barchart

• 1 Ultra-High Risk Signal Just Triggered for the Stock Market. How to Profit from It.
• Wedbush Just Raised Its Price Target on Micron Stock by 56% Ahead of March 18. Should You Buy It Now?
• Oklo Just Scored an NRC License. Should You Buy OKLO Stock Here?
• Nebius Just Scored Another Key Partnership. Should You Chase NBIS Stock Here?