"An excellent advocate who is very good with clients and has great expertise in matters with international aspects – Swiss matters in particular."
Chambers Global 2014


Mark Hanchet’s practice at Mayer Brown focuses on commercial litigation, arbitration, complex business litigation, securities litigation, bankruptcy litigation and regulatory enforcement, primarily involving financial institutions. He serves as one of the Firm’s Group Leaders for International Banking and Financial Services Litigation. Mark has experience in all phases of litigation, not only at the trial and appellate levels in federal and state courts, but also in various alternative dispute resolution forums.

Much of Mark’s financial services practice is international in nature; he routinely represents banks in connection with cross-border litigation and in proceedings seeking attachments and injunctions concerning assets located in the US and abroad. He also advises clients on a variety of issues relating to international dispute resolution, including forum selection, jurisdiction, service of process, and he is well-versed in navigating international discovery and judgment enforcement issues.

Representative financial services clients in recent matters include the following institutions and their affiliates: Ally Bank; Associated Bank; Banca Monte dei Paschi di Siena SpA; Banco de Chile; Bank Leumi; Bank Hapaolim; Bank of New York; Banque Libano-Française SAL; Bayerische Landesbank; BNP Paribas; CIBC; Citibank; Credit Suisse; HSBC; IKB; Mizuho Bank, Ltd.; MKB Bank; Pictet; Schroders; Société Générale; Stanbic Bank; Standard Bank of South Africa; Sumitomo Mitsui Banking Corp.; Toronto Dominion Bank; and UBS.

Mark also represents a wide range of clients involved in litigation flowing from complex business transactions. He recently has provided legal counsel and representation to the following entities and their affiliates in various engagements: ABB, Inc.; Cargill; Ion Media Networks; Macquarie; Merrill Lynch; Nestle, S.A., Penson Worldwide, Inc.; Starwood Capital Group; Swisscom; Toyota Motors; and Unilever.

Mark joined Mayer Brown in 2005. Previously, he was a partner with another prominent law firm in New York. He speaks French, English, and has a working knowledge of German.

Spoken Languages

  • English
  • French
Securities Investigations: Internal, Civil and Criminal


  • Mark served as lead litigation counsel on behalf of a prominent securities institution, successfully defending a case seeking damages in excess of $200 million, based on allegations that the prime broker client was instrumental in a hedge fund principal’s investor fraud.
  • In an action in which an international bank was accused of participating in a US fraud and violating the substantive laws of its home country resulting in alleged damages of over $47 million, Mark served as lead litigation counsel on behalf of the bank, obtaining dismissal of the complaint on forum non conveniens grounds.
  • An international bank alleged to have been involved in helping a foreign government fugitive launder and otherwise secrete stolen government assets, tapped Mark as lead litigation counsel.  Plaintiffs sought damages from the bank in excess of $100 million; the case was dismissed in its entirety.
  • Mark served as lead litigation counsel, advising an international financial institution with custody of over $120 million in assets held in the name of a judgment debtor’s affiliate; this high profile representation implicated thorny issues of jurisdiction, comity and international discovery. 


Université de Strasbourg III, DEA

McGill University, BCL, LLB
Editor, Law Journal

McGill University, BA


  • New York


  • US District Court for the Southern District of New York
  • US District Court for the Eastern District of New York
  • US Court of Appeals for the Second Circuit
  • US Court of Appeals for the Eleventh Circuit
  • US District Court for the Western District of New York
  • US Court of Appeals for the Seventh Circuit