Professional Biography
Image of Sean Knowles

Sean C. Knowles Partner

Firmwide Chair, Securities Litigation Practice

  • Seattle

    D +1.206.359.6224

    F +1.206.359.7224


    1201 Third Avenue, Suite 4900

    Seattle, WA 98101-3099




Sean Knowles focuses his practice on securities litigation, corporate governance matters and white collar investigations and defense. Sean regularly represents public companies and their officers and directors in shareholder class action litigation, mergers and acquisition litigation, United States Securities and Exchange Commission (SEC) enforcement proceedings and investigations, and shareholder derivative lawsuits. Sean has represented numerous clients defending claims under the Washington State Securities Act. Sean has also counseled public companies and corporate directors on corporate governance matters.

Sean has represented clients in shareholder class actions alleging securities fraud in federal courts. Sean has represented clients in various securities litigation arising from the mortgage-related financial crisis, including the consolidated multidistrict litigation captioned In re Washington Mutual, Inc. Securities, Derivative & ERISA Litigation in the Western District of Washington. Sean also represented a major accounting firm in connection with federal securities fraud claims and concurrent regulatory and foreign criminal investigations.

Sean has represented clients in connection with investigations by the SEC, United States Department of Justice (DOJ), and state attorneys general, as well as shareholder books and records inspection demands, FINRA inquiries and substantiation of confidentiality requests under the Freedom of Information Act (FOIA). Sean has advised clients on Foreign Corrupt Practices Act compliance and related corporate governance issues. Sean represented a Fortune 50 pharmaceutical company in confidential grand jury proceedings and related qui tam litigation under the False Claims Act and has conducted internal investigations in the pharmaceutical and insurance industries, among others.

Professional Recognition

  • Listed in Best Lawyers in America 2016 - 2022: Litigation - Securities

Related Employment

  • Bloomberg LP, Chicago, IL, Legal Analyst, 2007
  • Davis Polk & Wardwell LLP, New York, NY, Litigation Associate, 1999 - 2006
  • State of Rhode Island District Court, The Hon. Gilbert V. Indeglia, Providence, RI, Intern, 1996





Bar and Court Admissions

  • Washington
  • New York
  • U.S. Court of Appeals for the Ninth Circuit
  • U.S. Court of Appeals for the First Circuit
  • U.S. District Court for the Western District of Washington
  • U.S. District Court for the Eastern District of Washington


  • Columbia Law School, J.D., 1999
  • Brown University, A.B., Psychology and Political Science, 1996