Samir Deger-Sen

Practice Areas

Samir Deger-Sen, an experienced appellate lawyer, represents clients in their most complex litigation matters.

Samir focuses his practice on Supreme Court and appellate litigation and is widely recognized as one of the leading appellate lawyers of his generation. He has argued over 30 times in appellate courts across the US, including multiple arguments in the Supreme Court, and successfully represented clients in the technology, media, and financial sectors in their highest-stakes appeals.

Samir has extensive experience in the New York appellate courts. He has argued eight times in the US Court of Appeals for the Second Circuit, where he has never lost a case, and led over a dozen appeals in the New York state courts. He is one of a handful of attorneys who has argued multiple times in both the US Supreme Court and the New York Court of Appeals, the state’s highest court.

He also has significant experience in class actions and is proficient in substantive Rule 23 law. Samir has been the primary author of briefs involving some of the largest putative classes in the country, including defending clients against multi-billion dollar class actions in the Second and Ninth Circuits. He has, on multiple occasions, successfully secured interlocutory appellate review of class certification decisions, which is granted in only a small fraction of cases. He also regularly advises on complex class action issues in district court litigation.

In addition, Samir has successfully obtained complete dismissal of claims in over a dozen securities class actions on appeal, including multiple times in the Second and Ninth Circuits.

Resident in the firm’s New York and London offices, Samir frequently helps UK-based clients navigate novel, complex, and challenging questions of US law.

Before entering private practice, he clerked for Justice Anthony Kennedy of the US Supreme Court, on the Ninth Circuit Court of Appeals, and on the District Court for the District of Hawaii. Before law school, Samir was a lecturer in International Politics at Oxford University, where he taught several undergraduate level courses. At Oxford, he won the World University Debating Championship, along with numerous national competitions.