Negotiations have broken down in attempts to settle a sprawling class-action race discrimination case brought by black managers against Sodexho Inc., one of the region's largest employers, a mediator told a federal judge yesterday.

The Gaithersburg-based food service and facilities management company had been in private negotiations with the lead plaintiffs in the suit since August. But those discussions have not led to a settlement, and the talks were at an impasse, U.S. District Judge Ellen Segal Huvelle was told yesterday in an hour-long hearing in Washington.

Huvelle certified the suit as a class-action case in July, then set a series of hearing dates to prepare the case for trial. Both sides said that talks might resume.

"We think it's important to point out the court has not ruled on the merits of the case, and when it does, we are confident they will determine that Sodexho does not discriminate," said company spokeswoman Leslie Aun.

In one of the largest race discrimination class-action suits since U.S. civil rights laws were bolstered by Congress in 1991, the plaintiffs allege that the 130,000-employee company has a "pattern and practice" of denying promotions and deserved advancements to black mid-level executives. Attorneys for the company have denied the claims in court filings.

The case hinges upon allegations of black employees that the company's lack of a consistent system of internal job applications and promotions, with few written records, allowed subtle or overt racism to influence almost every hire into upper management.

In interviews and in court filings, the lead plaintiffs say that only 1.9 percent of the company's regional and executive positions are held by blacks, a percentage far below blacks' overall numbers in the company, and that this formed a corporate "glass ceiling" that keeps them at mid-level management positions.

Huvelle agreed in July that the plaintiffs had made a "significant showing" of discrimination and permitted them to move forward in a class-action lawsuit, expanding the case's reach to include 2,600 black current and former Sodexho employees.

"Right now, the mediator has declared an impasse," said Kerry Scanlon, the plaintiffs' attorney. "If either side wants to, we can go back to the table. But for now, we're on a schedule that would lead us to trial."