Alexander Costin is an associate in the Litigation Department, where his practice focuses on complex commercial litigation, including contract disputes, employment matters, and ESG-related litigation. In October 2026, Mr. Costin received a “Litigator of the Week” shout-out from The American Lawyer. He also maintains an active pro bono practice, representing nonprofit and community-based organizations in New York City.

Mr. Costin joined Debevoise in 2023. He previously clerked for the Hon. Rosemary S. Pooler of the United States Court of Appeals for the Second Circuit and for the Hon. John G. Koeltl of the United States District Court for the Southern District of New York.

Mr. Costin received a J.D. in 2020 from Stanford Law School, where he was an articles editor of the Stanford Law Review. He received an A.B. summa cum laude and Phi Beta Kappa from Princeton University in 2017.

Mr. Costin is a member of the Bars of New York and New Jersey and is admitted to practice before the U.S. Courts of Appeals for the First and Second Circuits and the U.S. District Courts for the Southern and Eastern Districts of New York.