Wachtell, Lipton, Rosen & Katz asked a California court to compel arbitration of a lawsuit from Twitter parent company X Corp. that takes issue with some $90 million in legal fees allegedly paid to Wachtell for its representation of Twitter in merger and acquisition litigation against Elon Musk.

The motion, filed by Morrison & Foerster partners Ragesh Tangri and Jordan Eth on behalf of Wachtell in California Superior Court in San Francisco on Friday, claims Twitter’s lawsuit should never have been filed in the California court given an arbitration clause in a master retention agreement between Twitter and Wachtell.