3 Inflated Stocks with Questionable Fundamentals

Each stock in this article is trading near its 52-week high. These elevated prices usually indicate some degree of investor confidence, business improvements, or favorable market conditions.

However, not all companies with momentum are long-term winners, and many investors have lost money by following short-term trends. On that note, here are three stocks that are likely overheated and some you should look into instead.

Mayville Engineering (MEC)

One-Month Return: +14.2%

Originally founded solely on tool and die manufacturing, Mayville Engineering Company (NYSE:MEC) specializes in metal fabrication, tube bending, and welding to be used in various industries.

Why Are We Cautious About MEC?

1. Annual sales declines of 3.1% for the past two years show its products and services struggled to connect with the market during this cycle
2. Gross margin of 12.8% is below its competitors, leaving less money to invest in areas like marketing and R&D
3. Earnings per share have contracted by 52.4% annually over the last two years, a headwind for returns as stock prices often echo long-term EPS performance

Mayville Engineering’s stock price of $19.02 implies a valuation ratio of 81x forward P/E. Read our free research report to see why you should think twice about including MEC in your portfolio.

MasTec (MTZ)

One-Month Return: +15.4%

Involved in the 1996 Olympic Games MasTec (NYSE:MTZ) is an infrastructure construction company that specializes in the telecommunications, energy, and utility industries.

Why Does MTZ Fall Short?

1. Gross margin of 12.9% reflects its high production costs
2. Operating margin of 3.1% fell from an already low starting point over the last five years because it pursued growth instead of profits
3. 4.2 percentage point decline in its free cash flow margin over the last five years reflects the company’s increased investments to defend its market position

At $228.12 per share, MasTec trades at 29x forward P/E. Check out our free in-depth research report to learn more about why MTZ doesn’t pass our bar.

Ally Financial (ALLY)

One-Month Return: +12.6%

Born from the former GMAC (General Motors Acceptance Corporation) and rebranded in 2010, Ally Financial (NYSE:ALLY) operates a digital-first bank offering auto financing, insurance, mortgage lending, and investment services to consumers and commercial clients.

Why Do We Avoid ALLY?

1. Flat sales over the last two years suggest it must find different ways to grow during this cycle
2. Sales over the last two years were less profitable as its earnings per share fell by 2.6% annually while its revenue was flat
3. Low tier one capital ratio of 9.7% indicates the company may struggle to maintain adequate liquidity during periods of economic stress

Ally Financial is trading at $44.45 per share, or 8.7x forward P/E. If you’re considering ALLY for your portfolio, see our FREE research report to learn more.

Stocks We Like More

The market’s up big this year - but there’s a catch. Just 4 stocks account for half the S&P 500’s entire gain. That kind of concentration makes investors nervous, and for good reason. While everyone piles into the same crowded names, smart investors are hunting quality where no one’s looking - and paying a fraction of the price. Check out the high-quality names we’ve flagged in our Top 9 Market-Beating Stocks. This is a curated list of our High Quality stocks that have generated a market-beating return of 244% over the last five years (as of June 30, 2025).

Stocks that made our list in 2020 include now familiar names such as Nvidia (+1,326% between June 2020 and June 2025) as well as under-the-radar businesses like the once-small-cap company Comfort Systems (+782% 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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