Susan S. Muck

Co-Chair, Securities Enforcement

Partner, Securities Litigation  

San Francisco 415.875.2325


Susan Muck handles shareholder actions, SEC enforcement proceedings and regularly advises boards and management on disclosure and accounting issues, the Foreign Corrupt Practices Act and other high-profile governance matters. She has conducted internal investigations into alleged bribery and accounting fraud for multinational corporations and represented companies and individuals in SEC investigations and at trial. Her extensive experience defending shareholder class actions includes winning the dismissal of General Electric-InVision in securities litigation arising out of the settlement of FCPA investigations by the DOJ and SEC, a result that was affirmed by the Ninth Circuit in Glazer Capital Management, LP v. Magistri, 549 F.3d 736 (2008). She also won the dismissal of a shareholder class action against biotech firm Immersion Corporation arising out of an internal investigation and multi-year restatement, a result that was also affirmed by the Ninth Circuit in Loos v. Immersion Corp., 762 F.3d 880 (2014).

Recent accolades:

  • Chambers USA 2018 Securities Litigation-California: Susan “embraces difficult situations and possesses great analytical skills that provide value to her clients”
  • The Legal 500 2018: Susan “has gravitas and experience that are practically unmatched”; named to list of top securities litigation lawyers in the U.S.
  • Best Lawyers 2017, The Best Lawyers in America: recognized for excellence in commercial litigation
  • Chambers USA 2017 Securities Litigation-USA: Susan was lauded by clients as a “fierce litigator,” who combines her "very deep technical knowledge" with "tremendous attention to client service"

Susan has been repeatedly recognized as one of the top litigators in California by The Best Lawyers in America, and Northern California Super Lawyers and as one of the “Top 100 Lawyers” and “Top Women Lawyers” by the Daily Journal. She was named a Best Lawyers “Lawyer of the Year,” which honors a single lawyer in a practice area in each community. She is also a Law360 Securities MVP for her work on behalf of Immersion and in connection with the defense and settlement of the Diamond Foods governmental investigations and the innovative settlement she reached in Diamond’s shareholder litigation. The Diamond Foods’ resolution was cited as a key factor in Fenwick’s Securities Litigation team being named “Securities Litigation Department of the Year” by The Recorder over 20 other California firms in 2013.

A dedicated member of the legal community, Susan is a founding member of Women in Securities (WISe), a network for women securities litigators.

Regulatory and Internal Investigations and Enforcement Proceedings

  • Defense of publicly disclosed accounting, FCPA or insider trading investigations for LendingClub, General Electric-InVision (non-prosecution agreement), RAE Systems (no enforcement action), Connetics (no enforcement action), Sunrise Telecom (no enforcement action), Immersion (no enforcement action) and Diamond Foods (settlement)
  • Investigated publicly disclosed compensation-based allegations against Equinix, Extreme Networks, MIPS, Sunrise Telecom, Zoran and many other public companies, concluding all regulatory inquiries with no enforcement action
  • Represented RS Investments in SEC and Attorney General investigations involving alleged mutual fund market timing
  • Successfully defended Morgan Stanley Dean Witter in trial against the SEC challenging the scope of supervisory requirements and procedures

Shareholder Litigation

  • Defending Chegg, GoPro, Sunrun, Nimble Storage and other technology companies in federal and state securities and derivative suits
  • Defended InVision-General Electric in securities class actions arising from FCPA investigations by the DOJ and SEC; dismissal affirmed by the Ninth Circuit
  • Defended Barclays, Castlight Health, Diamond Foods, Electronic Arts, Equinix, Intuit, the Board of Las Vegas Sands, LendingClub, Model N, ShoreTel and Vocera in shareholder class or derivative litigation alleging accounting or disclosure violations
  • Defended life sciences companies Connetics, Immersion and Sunrise Medical in securities litigation arising out of multi-year restatements and alleged improper revenue recognition
  • Defended Affymetrix, Equinix, Extreme Networks, F5, MIPS and Zoran in shareholder litigation arising out of alleged stock option backdating
  • Represents multiple special committees investigating or defending shareholder derivative demands, including for the board of Sempra Energy and Microsoft. Susan’s representation of the special committee of California Micro Devices’ Board of Directors resulted in the leading California opinion on the conduct of special litigation committees, Desaigoudar v. Meyercord, 108 Cal. App. 4th 173 (2003)


  • Susan has developed FCPA, UK Bribery Act and general ethics and compliance programs for dozens of public and private companies.
  • She has lectured and written extensively on compliance issues, most recently for the Association of Corporate Counsel, Compliance Week, Law 360, Northwestern University and Stanford University.