
Many investors pay attention to mid-cap stocks because they have established business models and expansive market opportunities. However, their paths to becoming $100 billion corporations are ripe with competition, ranging from giants with vast resources to agile upstarts eager to disrupt the status quo.
These dynamics can rattle even the most seasoned professionals, which is why we started StockStory - to help you separate the good companies from the bad. That said, here is one mid-cap stock with a long growth runway and two that could be down big.
Market Cap: $13.3 billion
Headquartered just outside of Detroit, MI, Masco (NYSE:MAS) designs and manufactures home-building products such as glass shower doors, decorative lighting, bathtubs, and faucets.
Why Do We Think MAS Will Underperform?
At $67.81 per share, Masco trades at 15.5x forward P/E. Dive into our free research report to see why there are better opportunities than MAS.
Market Cap: $11.77 billion
With a research department that makes over 10,000 property updates daily to its 35-year-old database, CoStar Group (NASDAQ:CSGP) provides comprehensive real estate data, analytics, and online marketplaces for commercial and residential properties in the U.S. and U.K.
Why Are We Cautious About CSGP?
CoStar’s stock price of $29.24 implies a valuation ratio of 19.2x forward P/E. To fully understand why you should be careful with CSGP, check out our full research report (it’s free).
Market Cap: $12.57 billion
Based in Texas and founded over a century ago, Lennox (NYSE:LII) is a climate control solutions company offering heating, ventilation, air conditioning, and refrigeration (HVACR) goods.
Why Do We Like LII?
Lennox is trading at $363.61 per share, or 14.5x forward P/E. Is now a good time to buy? Find out in our full research report, it’s free.
ONE MORE THING: Top 6 Stocks for This Week. This market is separating quality stocks from expensive ones fast. AI is taking down whole sectors with no warning. In a rotation this fast, you need more than a list of good companies.
Our AI system flagged Palantir before it ran 1,662% between October 2022 and February 2026. AppLovin before it ran 753% between February 2024 and February 2026. Nvidia before it ran 1,178% between January 2023 and February 2026. Each week it produces 6 new names that pass the same tests. Get Our Top 6 Stocks for Free HERE.
Stocks that made our list in 2020 include now familiar names such as Nvidia (+1,460% between June 2020 and June 2025) as well as under-the-radar businesses like the once-micro-cap company Kadant (+214% between June 2020 and June 2025). Find your next big winner with StockStory today.