About Brendan P.
Brendan P. Cullen built a legal foundation at the University of Oregon, earning his B.A. in 1991, and then at Stanford Law School, where he received his J.D. in 1995. His academic record placed him on a familiar path to federal courts and major firm practice.
Early in his career he clerked for Judge Laurence H. Silberman on the U.S. Court of Appeals in 1995, then spent a year as a law clerk to Justice Clarence Thomas at the United States Supreme Court in 1996. Those two clerkships gave him direct exposure to appellate reasoning at the highest levels and shaped his understanding of federal procedure and constitutional argument.
In 1997 he joined Sullivan & Cromwell LLP. He has remained at the firm since then and serves as a partner. At Sullivan & Cromwell he has worked on matters that engage complex legal questions and often involve multi-jurisdictional issues. Colleagues describe him as methodical and precise in briefing and motions work, and he has regularly appeared in team representations handled by the firm.
Cullen also participates in community and professional organizations. He sits on the boards of the Silicon Valley Campaign for Legal Services, the Atherton Police Foundation and the Stanford Law School Board of Visitors. He is a member of the Federal Bar Association and has been a member of the California State Bar since 1998. Those roles keep him involved in legal access initiatives, local civic concerns and legal education policy.
Across his career he has moved between appellate work and large-firm litigation practice. His clerkships informed his approach to complex briefing and appellate strategy, while his years at Sullivan & Cromwell have involved coordinated work on multi-party, often high-stakes matters. He has combined appellate experience with practice at a national law firm environment.
He is admitted to practice in California and maintains his practice through Sullivan & Cromwell LLP. He practices in California and continues to represent clients in matters arising in that jurisdiction.
