Irell & Manella is abandoning most of its transactional practices in an effort to focus solely on high-value litigation work, in a move that’s already led to the departure of three partners this week.

Michael Kaplan and Gregory Klein departed from the Los Angeles-based Am Law 200 law firm this week after learning that it wasn’t going to support growing their mergers and acquisitions practice. They joined Simpson Thacher & Bartlett. A third lawyer, Harry Mittleman, is bringing his commercial litigation practice to Hueston Hennigan.