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Brian Klein is an accomplished trial attorney who has successfully litigated in federal and state court. His practice focuses on high-stakes criminal and regulatory defense matters and civil litigation, and he aggressively and effectively advocates for his clients in a wide variety of state and federal forums. He is a former federal prosecutor with extensive trial experience, and he is known for his superior courtroom skills. He teaches a criminal practice seminar at the USC Gould School of Law.  

Brian often represents successful entrepreneurs and professionals, iconoclastic companies, celebrities, and high-profile start-ups and fast growing businesses in connection with the most important legal issues facing them whether civil, regulatory, or criminal. As an example, he presently represents Marcus Hutchins, who is worldwide hero due to his assistance stopping the “WannaCry” ransomware attack in May 2017, in a prosecution based out of the Eastern District of Wisconsin for cyber-related crimes dating back to 2014-15. As another example, he currently represents Arthur and Kathleen Breitman, as well as their company, in connection with securities class action lawsuits involving the Tezos crowdfunding, which raised over $230 million. He also successfully defended Cesar Millan (the “Dog Whisperer”) when the Los Angeles County Department of Animal Control and District Attorney’s Office investigated allegations of animal abuse tied to one of Mr. Millan’s television shows. The authorities ultimately concluded Mr. Millan did nothing wrong and did not bring any charges. Based on his accomplishments, Brian has been repeatedly recognized as a “Super Lawyer” (including for 2018 as a Top 100 lawyer overall in Southern California) and he is frequently sought ought by the media to comment on pressing legal issues.

He has extensive experience with cutting-edge technology cases, including representing entrepreneurs, start-ups, and early adopters in all types of criminal and regulatory defense matters and civil litigation (including bankruptcy proceedings). He founded and chairs the board of directors of the non-profit Digital Currency and Ledger Defense Coalition and chairs the American Bar Association’s blockchain technology, digital currency, and ICO national institute, which will be held in New York City this year. He serves as an advisor to BlockSeer, a blockchain analytics company, and formerly volunteered as the outside general counsel and chair of the legal advocacy committee for the Bitcoin Foundation. He speaks about Fintech around the world at, among other places, global law firms, major payments and technology companies, and industry conferences. Chambers recently recognized as Brian as “the leading cryptocurrency trial attorney in the USA.”

Brian is admitted to practice in the states of California, Washington, and New York and before numerous federal courts around the country (including the Central and Northern Districts of California and the Southern and Eastern Districts of New York). He graduated from New York University School of Law and received his undergraduate degree from the University of Washington.

Representative Criminal and Civil Engagements:

  • Successfully defended a digital currency trader in federal court in Colorado against an unlicensed money transmitter criminal charge, securing dismissal of the case before trial.
  • Obtained a complete acquittal at a jury trial for a boxer charged with assault with a deadly weapon in state court.
  • Represented Erik Voorhees, a prominent early Bitcoin adopter, in his settlement with the SEC.
  • Secured from the Los Angeles County District Attorney’s Office a declination to charge a high-profile client accused of sexual assault by someone the client met on a dating app.
  • Represented a film production company in a federal action to enforce trademark rights that resulted in a settlement favorable to the client.
  • Successfully defended a digital currency company in a state securities division investigation based out of the Midwest (no enforcement action was brought).
  • Represented a U.S.-based technology company in a contract dispute with an Australian entertainment company that resulted in a settlement favorable to the client.
  • ​Successfully defended a hazardous waste cleanup company facing multiple state criminal charges, securing dismissal of all charges before trial.

Publications and Selected Speaking Engagements:

  • “Initial Coin Offerings: Where the SEC Might Stand, Coindesk (co-authored with Kobre & Kim), June 2017
  • Moderator, Legal & Policy Workshop on Regulatory and Enforcement Developments, Consensus 2017, New York, NY May 2017
  • Guest Lecturer, “Digital Currency, Blockchains, and the Future of the Financial Services Industry,” New York University School of Law and Stern School of Business, May 2017
  • Speaker, “Innovation vs. Regulation: Fintech’s Evolving Global Regulatory Landscape,” Seoul, South Korea, December 2016
  • Panelist, “Law Enforcement & Anonymous Transactions,” Consensus 2016, New York, NY, May 2016
  • “The Fifth Amendment and Bitcoin: Why the Battle is About to Begin,” Coindesk, February 2016
  • Panelist, “Enforcement Today – Case Examples,” The American Bar Association’s National Institute on Bitcoin and Other Digital Currencies, Washington, D.C., June 2015
  • “The CFTC’s Not-So-Hidden Message: Traders Beware,” Coindesk (co-authored with Sidley Austin), October 2015
  • “Does 18 U.S.C. § 1960 create felony liability for bitcoin businesses,” Coin Center, July 2015
  • Speaker, “Game Changers (Bitcoin),” Defense Research Institute’s Annual Conference, San Francisco, California, October 2014
  • “Why The SEC Delay Over Crowdfunding Rules Is Stifling Bitcoin Innovation,” Coindesk (co-authored with McGuireWoods), June 2014
  • Panelist, “Perspectives on Government Relations,” Bitcoin 2014: Building the Digital Economy (the Bitcoin Foundation), Amsterdam, Netherlands, May 2014
  •  “US Tax Man Speaks For The First But Not Last Time,” Coindesk (co-authored with Sideman & Bancroft), April 2014
  • Panelist, "Issues of Regulatory Compliance," Bitcoin 2013: The Future of Payments (Bitcoin Foundation), San Jose, California, May 2013
  • ​“Treasury Department Wary of Virtual Currencies,” The Daily Journal, April 2013

Professional Associations and Memberships:

  • American Bar Association
  • National Association of Criminal Defense Attorneys
  • Los Angeles County Bar Association
  • ​Board Member, Los Angeles Center for Law and Justice

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Brian Klein

Brian Klein.
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