SAN JOSE — Quinn Emanuel Urquhart & Sullivan escaped the most severe sanctions sought by its adversaries for a discovery leak that placed details of Apple’s licensing deal with Nokia in the hands of client Samsung. But the firm, known for its swagger, emerges from a bruising six-month sanctions fight with a chink in its reputation as a lean fighting machine.

Quinn’s famously spare structure, where associates work with minimal supervision, opened the door to a breach that went unremedied for more than a year and exposed Apple’s confidential business information to hundreds of unauthorized individuals, U.S. Magistrate Judge Paul Grewal concluded in a 19-page order sanctioning both the firm and Samsung for violating a court protective order.