Sifting through countless of stocks in the Machinery industry can be tedious, and sometimes two stocks are just too similar to judge which is the better investment. If you’re on the fence about investing in Trinity Industries, Inc., Proto Labs or Inc. because you’re not sure how they measure up, it’s important to compare them on a few factors before making your decision.

Read on to learn how Trinity Industries, Inc., Proto Labs and Inc. compare based on key financial metrics to determine which better meets your investment needs.

About Trinity Industries, Inc., Proto Labs and Inc.

Trinity Industries, Inc. provides railcar products and services under the TrinityRail trade name in North America. The company operates in two segments, Railcar Leasing and Services Group, and Rail Products Group. The Railcar Leasing and Services Group segment leases freight and tank railcars; originates and manages railcar leases for third-party investors; and provides fleet leasing, management, and administrative services, as well as railcar maintenance and modification services, and other railcar logistics products and services. As of December 31, 2025, it had a fleet of 101,485 railcars. This segment serves industrial shipper and railroad companies operating in refined products and chemicals, energy, agriculture, construction and metals, and consumer products. The Rail Products Group segment manufactures freight and tank railcars for transporting various liquids, gases, and dry cargo; and manufactures and sells railcars and related parts and components. This segment serves railroads, leasing companies, and industrial shippers of products in the refined products and chemicals, energy, agriculture, construction and metals, and consumer products markets. It sells or leases products and services through its own sales personnel and independent sales representatives. The company was incorporated in 1933 and is headquartered in Dallas, Texas.

Proto Labs, Inc., together with its subsidiaries, operates as a digital manufacturer of custom parts in the United States and Europe. It offers manufacturing services, such as molding, computer numerical control machining, 3D printing, and sheet metal to developers, engineers, and supply chain teams. The company was incorporated in 1999 and is headquartered in Maple Plain, Minnesota.

Latest Machinery and Trinity Industries, Inc., Proto Labs, Inc. Stock News

As of August 20, 2026, Trinity Industries, Inc. had a $2.4 billion market capitalization, compared to the Machinery median of $3.7 million. Trinity Industries, Inc.’s stock is up 12.7% in 2026, up 0.7% in the previous five trading days and up 5.76% in the past year.

Currently, Trinity Industries, Inc.’s price-earnings ratio is 7.0. Trinity Industries, Inc.’s trailing 12-month revenue is $2.0 billion with a 16.6% net profit margin. Year-over-year quarterly sales growth most recently was -4.2%. Analysts expect adjusted earnings to reach $2.225 per share for the current fiscal year. Trinity Industries, Inc. currently has a 4.2% dividend yield.

As of August 20, 2026, Proto Labs, Inc. had a $1.9 billion market cap, putting it in the 53rd percentile of all stocks. Proto Labs, Inc.’s stock is up 57.4% in 2026, down 13.3% in the previous five trading days and up 62.29% in the past year.

Currently, Proto Labs, Inc.’s price-earnings ratio is 62.5. Proto Labs, Inc.’s trailing 12-month revenue is $560.5 million with a 5.4% net profit margin. Year-over-year quarterly sales growth most recently was 10.5%. Analysts expect adjusted earnings to reach $2.214 per share for the current fiscal year. Proto Labs, Inc. does not currently pay a dividend.

How We Compare Trinity Industries, Inc., Proto Labs and Inc. Stock Grades

Stock evaluation requires access to huge amounts of data and the knowledge and time to sift through it all, make sense of financial ratios, read income statements and analyze recent stock movements. AAII created A+ Investor, a robust data suite that condenses data research in an actionable and customizable way suitable for investors of all knowledge levels, to help investors streamline and work through such data.

AAII’s proprietary stock grades come with A+ Investor. These offer intuitive A‐F grades for each of five key investing factors: value, growth, momentum, earnings estimate revisions and quality. Here, we’ll take a closer look at Trinity Industries, Inc., Proto Labs and Inc.’s stock grades to see how they measure up against one another.

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Trinity Industries, Inc., Proto Labs and Inc. Growth Grades

Company	Ticker	Growth
Trinity Industries, Inc.	TRN	D
Proto Labs, Inc.	PRLB	B

The foundation of growth investing is seeking out stocks of companies exhibiting strong, consistent and prolonged growth that is expected to continue into the future.

In order to compute the growth score and assign it a letter grade, the percentile ranks for each of three components‐consistency of annual sales growth, five-year sales growth rankings adjusted for extreme levels, and consistency of positive annual cash from operations‐must be determined. These three rank figures are added together, and the sum is ranked against the entire stock universe to arrive at a company’s Growth Score to create an equal distribution of grades.

The companies in the bottom 20% of the stock universe receive Growth Grades of F, considered to be very weak, while those in the top 20% receive A grades, which are considered very strong.

Trinity Industries, Inc. has a Growth Score of 30, which is Weak. Proto Labs, Inc. has a Growth Score of 73, which is Strong.

The Growth Grade Winner: Proto Labs, Inc.

As you can clearly see from the Growth Grade breakdown above, Proto Labs, Inc. has a more attractive growth grade than Trinity Industries, Inc.. For investors who focus solely on how a company is growing relative to other companies in the same industry, Proto Labs, Inc. could be a good stock to add to their portfolio. However, it’s important for investors to analyze multiple factors based on a wide range of metrics before deciding whether to buy.

Trinity Industries, Inc., Proto Labs and Inc.’s Quality Grades

Company	Ticker	Quality
Trinity Industries, Inc.	TRN	B
Proto Labs, Inc.	PRLB	A

Like the Value Grade, AAII’s A+ Investor Quality Grade comes from the percentile rank of key metrics. Specifically, the Quality Score is the percentile rank of the average of the percentile ranks of return on assets (ROA), return on invested capital (ROIC), gross profit relative to assets, buyback yield, change in total liabilities to assets, accruals, Z double prime bankruptcy risk (Z) score and the F-Score.

The score is variable, meaning it can consider all eight measures or, should any of the eight measures not be valid, the remaining measures that are valid. To be assigned a Quality Score, stocks must have a valid (non-null) measure and corresponding ranking for at least four of the eight quality measures.

The Quality Score is used to assess the underlying “quality” of a particular stock. A higher-quality stock possesses traits associated with upside potential and reduced downside risk. Backtesting of the Quality Grade shows that stocks with higher grades, on average, outperformed stocks with lower grades over the period of 1998 through 2019.

Stocks receive better grades (higher scores) for having higher scores for the quality subcomponents and worse grades (lower scores) for lower scores for the subcomponents.

Trinity Industries, Inc. has a Quality Score of 70, which is Strong. Proto Labs, Inc. has a Quality Score of 85, which is Very Strong.

The Quality Grade Winner: Proto Labs, Inc.

As you can clearly see from the Quality Grade breakdown above, Proto Labs, Inc. has a better overall quality grade than Trinity Industries, Inc.. For investors who are looking for companies with higher quality than others in the same industry, Proto Labs, Inc. could be a good stock to add to their portfolios. However, it’s important for investors to analyze multiple factors based on a wide range of metrics before deciding whether to buy.

Trinity Industries, Inc., Proto Labs and Inc.’s Estimate Revisions Grades

Company	Ticker	Earnings Estimate
Trinity Industries, Inc.	TRN	D
Proto Labs, Inc.	PRLB	A

Earnings estimate revisions scores consider the magnitude of a company’s earnings surprise in its last two reported fiscal quarters. Often, positive surprises beget further positive surprises‐or at least continued sales growth (the exact opposite is generally true, too).

Estimate revisions offer an indication of what analysts are thinking about the short-term prospects of a firm. Estimate revisions are based on the statistical significance of a firm’s last two quarterly earnings surprises and the percentage change in its consensus estimate for the current fiscal year over the past month and past three months.

Trinity Industries, Inc. has a Earnings Estimate Score of 24, which is Negative. Proto Labs, Inc. has a Earnings Estimate Score of 86, which is Very Positive.

The Earnings Estimate Revisions Grade Winner: Proto Labs, Inc.

As you can clearly see from the Earnings Estimate Revisions Grade breakdown above, Proto Labs, Inc. has a better Earnings Estimate Revisions Grade than Trinity Industries, Inc.. For those who are specifically looking for companies with better short-term prospects when compared to other companies in the same industry, Proto Labs, Inc. could be a good stock to invest in. However, it’s important to analyze multiple factors based on a wide range of metrics before deciding whether to buy.

Other Trinity Industries, Inc., Proto Labs and Inc. Grades

In addition to Growth, Estimate Revisions and Quality, A+ Investor also provides grades for Value and Momentum.

Momentum grades help uncover stocks experiencing anomalously high rates of return; research finds that stocks with high relative levels of momentum tend to outperform, whereas those with low levels of momentum tend to continue underperforming.

Successful stock investing involves buying low and selling high, so stock valuation is an important consideration for stock selection. Buying stocks that are going to go up typically means buying stocks that are undervalued in the first place, although momentum investors may argue that point.

These 2 key factors, when combined with the above, provide a holistic view into a particular stock. Further, by joining A+ Investor you can see whether Trinity Industries, Inc., Proto Labs and Inc. pass any of our 60+ stock screens that have outperformed the market since their creation.

So, Which Is the Better Investment, Trinity Industries, Inc., Proto Labs or Inc. Stock?

Overall, Trinity Industries, Inc. stock has a Growth Score of 30, Estimate Revisions Score of 24 and Quality Score of 70.

Proto Labs, Inc. stock has a Growth Score of 73, Estimate Revisions Score of 86 and Quality Score of 85.

Comparing Trinity Industries, Inc., Proto Labs and Inc.’s grades, scores and metrics can act as a solid basis to determine whether they may be a good investment or not. You’ll also want to look at your portfolio’s asset allocation as well as your risk tolerance and financial goals to see if either of these stocks would make a good fit for you. AAII can help you figure out which investments align with your individual needs and preferences.

Investors are encouraged to do their own due diligence and research. In this way, individuals can effectively become managers of their own assets‐without having to rely on others for financial independence. You can count on AAII for timeless articles on financial planning and stock-picking, unbiased research and actionable analysis.

A+ Investor adds to our qualitative teaching with a powerful data suite to help you whittle down investment choices to find stocks, exchange-traded funds (ETFs) or mutual funds that meet your needs.

AAII Disclaimer

We make no representations or warranties that any investor will, or is likely to, achieve profits similar to those shown, because past, hypothetical or simulated performance is not necessarily indicative of future results. Before making an investment decision, you should consider your circumstances and whether the information on our content is applicable to your situation. This information was prepared in good faith, and we accept no liability for any errors or omissions. The full disclaimer can be read here.