OAKLAND, Calif. - Alphabet Inc's Google must face all but one antitrust allegation about its online advertising business brought in a lawsuit by attorneys general for Texas and 16 other states or territories, a federal judge ruled on Tuesday.

Google won its motion to dismiss an allegation that a cooperation agreement it struck with Meta Platforms' Facebook in 2018 was an unlawful restraint of trade, with U.S. District Judge P. Kevin Castel saying the companies had valid business reasons for the deal.

Google failed to convince Castel to dismiss three other counts related to its market power, though the judge found that some underlying claims by the states lacked merit.

Google said in a blog post on Tuesday that the decision underscored how Texas' case "is deeply flawed."

Texas' attorney general's office did not immediately respond to a request for comment.

The antitrust case is one of several against Google and other big tech companies that could go to trial over the next couple of years.

(Reporting by Paresh Dave; Editing by Richard Pullin)