Samir Deger-Sen is an experienced appellate lawyer, who 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 20 times in appellate courts across the country, including multiple arguments in the US Supreme Court, and successfully represented clients in the technology, media, and financial sectors in their highest-stakes appeals. In the past two years, he has been named four times in The American Lawyer’s Litigator of the Week feature, including for his successful arguments on behalf of Meta Platforms, the Hollywood Foreign Press Association, and Brigade Capital Management. He has been recognized by Law360, Bloomberg Law, and Lawdragon as one of the top appellate attorneys nationwide under the age of 40.

Samir has been a primary author of more than one hundred briefs involving a wide range of constitutional, statutory, and administrative law issues. In the Supreme Court, he has been a lead brief writer in multiple merits cases, has successfully persuaded the Court to grant certiorari on several occasions, and has been lead counsel to national organizations filing amicus briefs before the Court. He also has significant trial-level experience, including first chairing depositions, drafting and arguing dispositive motions, and authoring critical briefs in numerous international arbitrations. Samir is resident in both the firm’s New York and London offices and is available to help UK-based clients navigate novel, complex, and challenging questions of US law.

Samir has particular experience in class actions and is proficient in substantive Rule 23 law. He 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. Notably, Samir 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 significant experience in securities appeals. Over the past two years, he has successfully obtained complete dismissal of claims in several securities class actions on appeal in the Second and Ninth Circuits.

Samir has an extensive pro bono practice, where he has acted as lead counsel in high-profile constitutional litigation, including multiple precedent-setting victories in the Ninth Circuit.

Before entering private practice, Samir was a law clerk at all three levels of the federal judiciary. 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.

Samir has substantial public speaking experience. He is the winner of numerous national debating competitions and a former World University Debating Champion.

Samir’s representative experience includes:

  • Successfully persuaded the Supreme Court to grant certiorari and argued case deciding the appropriate remedy for violations of the Constitutional venue right 
  • Successfully persuaded the Supreme Court to grant certiorari and argued case-deciding availability of judicial review for revocation of an approved visa petition 
  • Successfully argued Second Circuit appeal for Brigade Capital Management, and obtained full dismissal, in case establishing the limit of the private right of action under the Investment Advisors Act 
  • Successfully argued Ninth Circuit appeal for a major technology company, and obtained full dismissal, in case substantially narrowing liability under the Telephone Consumer Protection Act 
  • Successfully argued Ninth Circuit appeal for the Hollywood Foreign Press Association, and obtained full dismissal, in case involving the scope of antitrust liability for membership organizations 
  • Successfully argued Ninth Circuit appeal for Pharmaniaga Berhad, obtaining full dismissal on personal jurisdiction grounds 
  • Successfully argued Second Circuit appeal for a software company, obtaining full dismissal of putative class action 
  • Argued or lead counsel in over 10 appeals in the New York State appellate courts, including multiple cases in the New York Court of Appeals 
  • Argued or led briefing in seven merits cases at the Supreme Court 
  • Successfully led the briefing in Seventh Circuit appeal for a software company in precedent-setting case involving applicability of arbitration clause to purported pseudonyms 
  • Leading the briefing in Seventh Circuit appeal for a major technology company in case involving scope of arbitration clause in putative consumer class action 
  • Arguing and leading the briefing on behalf of venture capital defendants in Second Circuit appeal involving the scope of liability under the securities laws for cryptocurrency exchanges 
  • Successfully obtained Rule 23(f) interlocutory review on three separate occasions, and led briefing on major class action disputes for a major technology company and Starkist 
  • Argued major constitutional challenge for a pharmaceutical company regarding drug pricing provision in the Inflation Reduction Act 
  • Led the briefing on over a dozen securities cases in the trial and appellate courts, including in the Second and Ninth Circuits 
  • Successfully argued multiple Ninth Circuit appeals representing certified class of individuals in immigration detention during COVID-19 

Bar Qualification

  • District of Columbia
  • England and Wales (Registered Foreign Lawyer)
  • New York

Education

  • JD, Yale Law School
  • MPhil in International Relations & Global Studies, The University of Oxford, Balliol College
    with distinction
  • BA (Hons) Philosophy, Politics and Economics, The University of Oxford, Balliol College
November 3, 2023 Recognition

Appellate Hot List — Winner

Firm recognized for continuing to succeed in first-of-their-kind cases while focusing on developing the next generation of appellate lawyers.

Blurry vision of the sun reflected in the glass skyscraper.
September 18, 2023 Recognition

Litigator of the Week Runners-Up and Shout Outs

Latham team recognized for its representation of client Brigade Capital Management LP in a Second Circuit win that has major implications for asset managers.