Cravath, Swaine & Moore partner Lauren Rosenberg argued on behalf of Morgan Stanley and a group of other major banks in the U.S. Court of Appeals for the Second Circuit on Monday, as the financial institutions asked the court to uphold a Manhattan federal judge’s dismissal of an antitrust suit brought by SL-x, the creator of an electronic stock lending platform.

SL-x sued the financial institutions for alleged antitrust violations in 2018, accusing them of engaging in an illegal boycott. U.S. District Judge Richard Sullivan of the Southern District of New York granted the defendants’ motions to dismiss, finding that SL-x’s claims were time-barred.