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Gregory Mortenson

Counsel

212.701.3708
gmortenson@cahill.com
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Cahill Gordon & Reindel LLP
32 Old Slip
New York, NY 10005

Practices

Education

  • Seton Hall University School of Law, J.D., 2013, magna cum laude; Editor-in-Chief, Seton Hall Law Review, Vol. 43
  • Georgetown University, B.S., 2006

Clerkships/Government Service

  • Honorable Esther Salas, United States District Court, District of New Jersey, 2014-2015
  • Honorable Jose L. Linares, United States District Court, District of New Jersey, 2015-2016

Admissions

  • New York
  • New Jersey

Gregory Mortenson is counsel in the New York office of Cahill Gordon & Reindel LLP where he focuses his practice on litigation & regulatory matters with an emphasis on digital assets, securities litigation, commercial litigation, and white collar defense & investigations.

An accomplished litigator & trial lawyer, Greg has handled matters for a wide roster of clients covering multiple substantive areas, including class actions, securities, contract disputes, M&A, fraud, fiduciary duty, conflicts of interest, tort, trade secrets, antitrust, and bankruptcy. Greg’s experience encompasses all phases of litigation and investigations—from initial case assessment through trial and appeal—on behalf of both plaintiffs and defendants, in fora around the country. Clients praise him for his tenacious yet pragmatic advocacy, and his successes have received numerous shout-outs in AmLaw’s coveted Litigator of the Week column. He is also frequent author and speaker on various noteworthy topics.

Prior to joining Cahill, Greg worked at a leading international law firm. He also brings to bear relevant in-house experience, having seconded at a global financial institution. He clerked in the U.S. District Court for the District of New Jersey, where he received the Clarkson S. Fisher award.

  • Global digital asset platform in securities class action stemming from high-profile collapse of competitor.
  • Global digital asset platform in Anti-Terrorism Act litigation.
  • Global digital asset platform in regulatory dispute concerning asset forfeiture.
  • DeFi token custodian concerning claims of commercial defamation and tortious interference.
  • Venture capital fund in multiple digital asset matters, including whether tokens are securities, liability of “decentralized autonomous organizations,” and solicitation liability under the Securities Act.*
  • Global digital asset platform in multiple matters, including securities class action regarding its direct listing and advising on litigation risk stemming from launch of DeFi product.*
  • Cryptographic key holder in federal class action relating to a DeFi bridge hack.*
  • Concert promoter in multiple matters, including: federal securities class action, derivative actions, and Section 220 demands regarding alleged failure to disclose anticompetitive conduct; and internal investigation, criminal investigation, Congressional inquiry, and multi-district litigation stemming from high-profile concert event resulting in multiple casualties.*
  • Investment manager in trial and appeal concerning sale of nearly $1bn in securities held in a CDO.*
  • Corporation and executive in trial and follow-on action involving tort, trade secret, and restrictive covenant claims.*
  • Global bank in internal investigation, government investigations, and multiple class actions alleging collusion in the bond market.*
  • Pharmaceutical company in federal securities class actions concerning allegedly noncompetitive drug pricing and opioid marketability.*
  • PE portfolio company in federal securities class action and derivative action regarding accounting restatement.*
  • Software company in parallel federal and state securities class actions regarding subscriber renewals.*
  • Semiconductor manufacturer in investigation, risk assessment, and litigation strategy related to cybersecurity incident surrounding M&A deal.*
  • Fintech executive in SEC enforcement action regarding alleged misstatements.*
  • Hedge fund in contract dispute with partner, within a bankruptcy proceeding.*
  • International clothing brand in contract dispute with key service provider.*
  • Energy company in post-merger contract dispute regarding valuation of net working capital and liabilities.*
  • Energy investment firm in trade secrets dispute.*
  • Former prisoner in pro bono trial and appeal regarding Eighth Amendment violations.*

*Matters handled prior to joining Cahill.