Pep Boys -- Manny, Moe & Jack investors will have to bide their time as a securities-law case works its way through federal court in Philadelphia, after a judge denied their bid to expedite document-gathering.

Three shareholders of the Philadelphia-based auto-parts company sued in U.S. District Court, and 10 suits were filed in the Pennsylvania Court of Common Pleas, challenging the fairness of a $1 billion, $15-a-share agreement in January to sell the company to venture capital firm Gores Group LLC.

Plaintiffs’ lawyers haven’t shown that delaying so-called discovery “will cause them undue prejudice,” Senior District Judge William H. Yohn Jr. wrote yesterday in an opinion.

Pep Boys fell more than 22 percent on May 1 after Los Angeles-based Gores asked the company to delay a May 30 shareholder vote on the deal because first-quarter results were below analyst estimates.

The vote was still scheduled. Shares fell 3 cents to $11.17 at 4:15 p.m. in New York Stock Exchange composite trading.

Brian Zuckerman, general counsel for Pep Boys, declined to comment on the ruling.

The federal case is Dipple v. Pep Boys, 12-cv-1415, U.S. District Court, Eastern District of Pennsylvania (Philadelphia).

To contact the reporters on this story: Phil Milford in Wilmington, Delaware, at pmilford@bloomberg.net, and; Dawn McCarty in Wilmington at dmccarty@bloomberg.net.

To contact the editor responsible for this story: Michael Hytha at mhytha@bloomberg.net