The S&P 500 (^GSPC) is often seen as a benchmark for strong businesses, but that doesn’t mean every stock is worth owning. Some companies face significant challenges, whether it’s stagnating growth, heavy debt, or disruptive new competitors.
Some large-cap stocks are past their peak, and StockStory is here to help you separate the winners from the laggards. That said, here is one S&P 500 stock that is leading the market forward and two that could be in trouble.
Two Stocks to Sell:
IDEX (IEX)
Market Cap: $12.09 billion
Founded in 1988, IDEX (NYSE: IEX) is a global manufacturer specializing in highly engineered products such as pumps, flow meters, and fluidics systems for various industries.
Why Should You Sell IEX?
- Organic sales performance over the past two years indicates the company may need to make strategic adjustments or rely on M&A to catalyze faster growth
- Sales over the last two years were less profitable as its earnings per share fell by 4% annually while its revenue was flat
- Eroding returns on capital suggest its historical profit centers are aging
IDEX is trading at $160.60 per share, or 18.8x forward P/E. If you’re considering IEX for your portfolio, see our FREE research report to learn more.
Regeneron (REGN)
Market Cap: $61.76 billion
Founded by scientists who wanted to build a company where science could thrive, Regeneron Pharmaceuticals (NASDAQ: REGN) develops and commercializes medicines for serious diseases, with key products treating eye conditions, allergic diseases, cancer, and other disorders.
Why Do We Think Twice About REGN?
- Sizable revenue base leads to growth challenges as its 5.9% annual revenue increases over the last two years fell short of other healthcare companies
- Efficiency has decreased over the last five years as its adjusted operating margin fell by 21.4 percentage points
- Diminishing returns on capital suggest its earlier profit pools are drying up
At $598.01 per share, Regeneron trades at 16.4x forward P/E. Read our free research report to see why you should think twice about including REGN in your portfolio.
One Stock to Buy:
TransDigm (TDG)
Market Cap: $72.99 billion
Supplying parts for nearly all aircraft currently in service, TransDigm (NYSE: TDG) develops and manufactures components and systems for military and commercial aviation.
Why Will TDG Beat the Market?
- Core business can prosper without any help from acquisitions as its organic revenue growth averaged 13% over the past two years
- Incremental sales significantly boosted profitability as its annual earnings per share growth of 24.9% over the last two years outstripped its revenue performance
- Impressive free cash flow profitability enables the company to fund new investments or reward investors with share buybacks/dividends, and its rising cash conversion increases its margin of safety
TransDigm’s stock price of $1,295 implies a valuation ratio of 30.8x forward P/E. Is now the time to initiate a position? See for yourself in our full research report, it’s free.
High-Quality Stocks for All Market Conditions
When Trump unveiled his aggressive tariff plan in April 2025, markets tanked as investors feared a full-blown trade war. But those who panicked and sold missed the subsequent rebound that’s already erased most losses.
Don’t let fear keep you from great opportunities and take a look at Top 6 Stocks for this week. This is a curated list of our High Quality stocks that have generated a market-beating return of 183% over the last five years (as of March 31st 2025).
Stocks that made our list in 2020 include now familiar names such as Nvidia (+1,545% between March 2020 and March 2025) as well as under-the-radar businesses like the once-micro-cap company Kadant (+351% five-year return). Find your next big winner with StockStory today for free. Find your next big winner with StockStory today. Find your next big winner with StockStory today
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