In case this article is the first thing you've read since yesterday afternoon, Apple wowed investors with a strong first-quarter earnings report after the bell on Tuesday. That sent the stock market vaulting out of the gates this morning, tempered only by some concerns raised by the Federal Reserve's forecasts on rates and the economy. Although the prospects of further monetary stimulus seem increasingly remote, investors bounced back from the hit, and the Dow Jones Industrials (INDEX: ^DJI) closed up 89 points to 13,091.

But it wasn't all smiles for the Dow 30. Let's focus on some Dow stocks that lost ground today.

Caterpillar (NYSE: CAT), down 4.7%
Apple wasn't the only company announcing earnings today. Caterpillar's news sounded good, but investors were apparently disappointed enough to send shares sinking.

Many companies would kill for the 29% profit growth and the 23% rise in revenue that the heavy-equipment manufacturer posted. A boost in profit guidance from $9.25 to $9.50 per share should have been icing on the cake. But as long as fears about China persist, Caterpillar will face pressure to show it can overcome a slowdown and use the emerging economy as a growth driver. Today's drop aside, how Caterpillar executes around the world will define its path in the years to come.

Wal-Mart (NYSE: WMT), down 0.8%
When bad news hits, it's time to cue the lawyers. Today, a shareholder brought a lawsuit against members of Wal-Mart's board and management following bribery allegations earlier this week against the company's Mexican division. Other law firms announced investigations that could eventually blossom into shareholder lawsuits as well.

The news isn't surprising. But it indicates that the company isn't going to get past this troubling news quickly or quietly. A long, drawn-out proceeding is the last thing even long-term shareholders want to deal with -- and that makes the ongoing declines in the shares easy to justify.

General Electric (NYSE: GE), down 0.5%
GE says it brings good things to life, but apparently not everyone's convinced. Protestors appeared at GE's annual shareholder meeting, demonstrating against the low taxes that the company has paid in recent years.

Of course, with the tax code allowing companies to carry losses forward to apply against profits in future years, GE is far from alone in paying little or nothing in taxes. Nevertheless, the protests reveal the negative public perception that GE's ill-timed foray into finance has earned the company.

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Fool contributor Dan Caplinger doesn't own shares of the companies mentioned. You can follow him on Twitter. The Motley Fool owns shares of Apple and Wal-Mart. Motley Fool newsletter services have recommended buying shares of Apple and Wal-Mart, as well as creating a bull call spread position on Apple and a diagonal call position on Wal-Mart. Try any of our Foolish newsletter services free for 30 days. We Fools don't all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Fool has a disclosure policy.