Sidley Austin LLP

With a wide range of litigation and arbitration experience, the team at Sidley Austin LLP supports a range of clients with complex business problems. Its expertise spans class actions, business torts, M&A litigation, securities and shareholder cases, and whistleblower actions. Bruce Braun, in Chicago, co-heads the team with Dallas-based Angela Zambrano. Braun’s practice includes antitrust, internal investigations, software litigation, and consumer fraud matters. Zambrano is noted for her arbitration work, and has particular experience in energy litigation and board of directors-level internal investigations. Yvette Ostolaza, also in Dallas, is recommended in complex, multi-jurisdictional commercial disputes. Brienne Letourneau joined the team from White & Case LLP in February 2025, in the Chicago office.