O’Melveny Worldwide

Bill Martin’s nearly two decades of government and private practice experience enables him to guide financial services companies, blockchain and other fintech companies, audit and special committees, officers and directors, and others in connection with internal investigations, government and regulatory inquiries and enforcement actions, and litigation.

A former senior counsel in the US Securities and Exchange Commission’s Market Abuse Unit, Bill has investigated and prosecuted securities cases involving insider trading, market-structure practices, the Foreign Corrupt Practices Act (FCPA), failure to supervise, investment advisors, and cybersecurity. In these matters, Bill worked closely with the Justice Department, FBI, IRS, FINRA, and other regulators.

Before entering public service, Bill spent six years in the litigation practice of a major New York law firm, advising clients in shareholder derivative and securities litigation and investigations. He frequently advised on cross-border matters and on litigation involving accounting fraud, internal controls, and other issues connected to the FCPA.

Read More

Private Practice Experience

  • Representing one of the largest digital-assets trading platforms in enforcement investigations by the Securities and Exchange Commission into potential registration violations
  • Advising digital-assets trading platforms and digital-assets project teams on potential legal and regulatory issues
  • Representing digital-assets project teams in investigations by DOJ, SEC and state financial services regulators
  • Represented a US bank in FINRA investigation into business referral practices of investment adviser affiliate; FINRA closed matter with no action taken
  • Represented a global bank in DOJ, SEC, and  IRS investigations into cross-border tax fraud
  • Represented a US bank in separate investigations by DOJ, OCC, the Federal Reserve, FDIC, multiple state AGs, and congressional committees into alleged foreclosure and mortgage-servicing deficiencies
  • Defended a Fortune 500 company against shareholder securities fraud claims, derivative and books-and-records cases brought against it in state and federal court relating to potential FCPA violations and a rejected merger offer; won five dismissals  

Selected Government Experience

  • FCPA, internal accounting controls, and books-and-records action related to conduct in India, China, and Kuwait
  • Insider trading action with profits in excess of $40 million
  • Investigated and led enforcement action charging antifraud violations of the Securities Exchange Act of 1934 and the Investment Advisers Act of 1940


Bar Admissions

  • New York

Court Admissions

  • US Court of Appeals, Second Circuit
  • US District Court, Eastern and Southern Districts of New York



  • University of Chicago Law School, J.D., with honors; Comment Editor, University of Chicago Law Review
  • Princeton University, Princeton School of Public and International Affairs, M.P.A., Domestic Public Policy  
  • Carleton College, B.A., magna cum laude, Economics and Political Economy


Honors & Awards

  • Three-time recipient of Director of Enforcement Division Award, Securities and Exchange Commission
  • Paul R. Carey Award, Securities and Exchange Commission

Professional Activities


  • Honorable Chester J. Straub, US Court of Appeals, Second Circuit 
  • Honorable P. Kevin Castel, US District Court, Southern District of New York


  • What the SEC’s Investigation of SolarWinds Means for CISOs and Cybersecurity Disclosures,” CPO Magazine (August 25, 2023)
  • “Decentralized Autonomous Organizations (DAOs): Overview,” Thomson Reuters Practical Law (November 29, 2022)
  • “Dismantling the SEC’s Federal Court Disgorgement Authority,” New York Law Journal (January 10, 2020)
  • “The SEC’s Crypto Moves are at Odds with its Own Mission,” PaymentsSource (July 2019)
  • “Is SEC disgorgement endangered? Supreme Court to decide,” Investment News (June 2019)
  • DC Circuit Upends SEC’s Low ‘Willful’ Standard for Securities Violation,” Bloomberg Law (May 2019)
  • “Supreme Court Rules That Class Was Not Properly Certified Because Plaintiffs Did Not Establish That Damages Could Be Measures on a Class-wide Basis,” Securities Reform Act Litigation (April 2013) 


  • “In the “Shadow” of Panuwat: SEC Insider Trading Unit Alumni Discuss Compliance Considerations Following Successful Shadow Trading Enforcement Action,” Practising Law Institute (June 11, 2024)

Corporate & Government Experience

  • Senior Counsel, Division of Enforcement, Market Abuse Unit, US Securities and Exchange Commission (2015-2019)