Wal-Mart Waits for a High-Stakes Ruling

"The main difference is just that it's a bigger case and national in scope," he said.

Should it lose the class certification and choose to settle the case, Wal-Mart could face two problems, said Morningstar's Brilliant. The first, of course, would be the financial impact of any sum it was forced to pay.

In the Home Depot case, the $87.5 million settlement was split among about 6,500 women, according to Borgen's firm. The average check was about $10,000, according to the firm. Applying similar numbers in the Wal-Mart case could take a potential settlement into the billions of dollars.

But beyond the financial impact is the black eye Wal-Mart would receive to its reputation if the suit ends badly for the company, Brilliant said. Socially responsible investors could shun the company, she said. And so might customers.

"This does call into question whether Wal-Mart is a good corporate citizen anymore," she said.

But other analysts are less concerned about the suit. Class-action suits about securities fraud used to draw a lot of headlines but turned out to be a nonevent for most companies and their stocks, noted Rob Wilson, who covers Wal-Mart for Tiburon Research Group. This suit is likely to have similar consequences, he said.

"I don't think it really impacts them," Wilson said. "Maybe it will drop the stock down a little bit, but I doubt it."