Gary M. Osen

Gary M. Osen, a member and the managing partner of the Firm, has litigated complex cases, often of international dimensions, throughout his career. He served as co-lead counsel in the leading case of Wortham v. KarstadtQuelle AG, which The Wall Street Journal described as “one of the largest single family Holocaust claims ever.” Currently, Mr. Osen serves as co-lead counsel in four major terrorism financing cases pending in federal courts: Linde v. Arab Bank, plc, Strauss v. Crédit Lyonnais, S.A., Weiss v. National Westminster Bank, Plc and Julin v. Chiquita Brands International, Inc.


Mr. Osen has also successfully represented hundreds of Nazi victims in their pursuit of legal claims against the German government and private entities, and has been involved in a wide variety of high profile cases addressing unusual and challenging legal issues.


Mr. Osen has what The Washington Times described as “a penchant for tackling larger-than-life cases” and developing new and creative legal theories that challenge some of the world’s largest companies and most powerful governments. The New York Times has recognized him as “an internationally consulted legal authority on terror financing.” He has been quoted and featured in most of the leading newspapers and magazines in the United States and around the world, including Time Magazine, The New York Times, The Wall Street Journal, The Times of London, The Economist, Der Spiegel and Haaretz. He has also appeared on CNN, the BBC, Bloomberg and Germany’s ARD and ZDF.  


Mr. Osen graduated from George Washington University Law School in 1992 and earned his undergraduate degree from Rutgers University with high honors in 1989. Mr. Osen also received an M.A. in Political Science from George Washington University in 1993. He is a member of the Bars in New York, Pennsylvania and New Jersey and is admitted to practice before the U.S. District Court for the District of New Jersey, the U.S. District Courts for the Eastern and Southern Districts of New York, the U.S. Court of Appeals for the Second Circuit and the United States Supreme Court.


  • Rutgers University (B.A., with high honors, 1989)
  • George Washington University, The National Law Center (J.D., 1992)
  • George Washington University (M.A., Political Science, 1993)
  • Undergraduate Fellow, Eagleton Institute for Politics, New Brunswick, New Jersey



  • U.S. District Court, District of New Jersey, 1993
  • U.S. Court of Appeals for the Third Circuit, 2003
  • U.S. District Court, Eastern District of New York, 2004
  • U.S. District Court, Southern District of New York, 2005
  • U.S. Court of Appeals for the Second Circuit, 2010
  • Supreme Court of the United States, 2013

  • U.S. District Court, District of Columbia, 2016


  • New Jersey, 1993
  • Pennsylvania, 1993
  • New York, 2003