A Facebook antitrust suit can move forward, a judge says, in a win for the F.T.C.

A federal judge on Tuesday allowed the Federal Trade Commission’s antitrust lawsuit against Facebook to move forward, rejecting Facebook’s request to dismiss the case and handing the agency a major victory in its quest to curtail the power of the biggest tech companies.

The judge, James Boasberg of the U.S. District Court of the District of Columbia, said last year that the F.T.C. had not provided sufficient evidence that the company, which has since named itself Meta, had a monopoly in social media and abused that power by harming competition. The agency refiled the case in August, and on Tuesday Judge Boasberg said that it had provided better support and that the lawsuit should move forward.

But he also included some caveats. Judge Boasberg said the agency could proceed with its claims that the company abused its monopoly power through acquisitions, which the agency has described as a “buy-or-bury” strategy. He dismissed, however, the agency’s charge that Facebook violated antitrust laws by cutting off third parties from its platform.

“Although the agency may well face a tall task down the road in proving its allegations, the court believes that it has now cleared the pleading bar and may proceed to discovery,” Judge Boasberg said.