MN 612-339-6900DC 202-544-9840
Slide background Slider Image Karen Hanson Riebel Partner
email vcard linkedin Securities Litigation Antitrust Law

Karen Hanson Riebel



Karen Hanson Riebel
email vcard linkedin print


Securities Litigation
Antitrust Law
Data Breach Litigation


Karen Hanson Riebel concentrates her practice in the areas of data breach, antitrust, and securities litigation. She has litigated a number of complex class action matters and represented numerous pension funds and other institutional investors in cases involving corporate fraud. Recently, she has been on the forefront of international data breach litigation, representing financial institutions against such retailers as Target and Home Depot.

Ms. Riebel began her career by spending seven months in Anchorage, Alaska as a member of the trial team that secured a jury verdict for punitive damages in the amount of $5 billion for a mandatory punitive damages class in In re The Exxon Valdez, Case No. A89-0095-CV (D. Alaska). For their efforts, Ms. Riebel and the other members of the trial team were awarded the Trial Lawyers’ For Public Justice Trial Lawyers of the Year award in 1994.

Representative Cases

  • Bank of Louisiana, et al. v. Equifax, Inc., 17-03715 (N.D. Ga.) - Counsel for Financial Institutions.
  • In re Arby's Restaurant Group, Inc. Data Security Litigation, 17-00514 (N.D. Ga.) - Co-Lead Counsel
  • In re Yahoo! Inc. Customer Data Security Breach Litigation, No. 16-02752 (N.D. CA) - Plaintiffs' Executive Committee
  • Shores et al v. Premera Blue Cross, No. 15-01268 (D. Or.) - Plaintiffs' Steering Committee
  • In re Target Corporation Customer Data Security Breach Litigation, No. 14-02522-PAM (D. MN) – Liaison Counsel for the Financial Institution Plaintiffs and member of Plaintiffs’ Leadership Committee
  • In re: Community Health Systems, Inc., Customer Security Data Breach Litig., No. 15-00222-KOB (N.D. AL) – Co-Lead Counsel
  • In re Home Depot, Inc., Customer Data Security Breach Litigation, No. 14-02583-TWT (N.D. GA) – Financial Institution Plaintiffs’ Steering Committee
  • In re: Supervalu, Inc., Customer Data Security Breach Litigation, MDL No. 2586 – Plaintiffs’ Executive Committee
  • First NBC Bank v. Kmart Corp. et al., No. 14-10088 (N.D. IL) - Co-Lead Counsel
  • Mertz v. Anthem et al., No. 15-00422-SEB/MJD (S.D. IN)
  • Kirk Dahl, et al., v. Bain Capital Partners, LLC, et al., (the Private Equity Antitrust Litigation), No. 07-CV-12388 (D. Mass.) – Resulted in recovery of $590.5 million for plaintiffs.
  • In re Payment Card Interchange Fee and Merchant Discount Antitrust Litigation, MDL No. 1720 (E.D. NY)
  • In re Worldcom, Inc. Securities Litigation No. 02-CV-3288 (S.D. NY) – Securities class action which resulted in recovery of $6.13 billion for plaintiffs.


  • The Exxon Valdez Experience presented at Louisiana State Bar Association¬ís Gulf Coast Oil Spill Symposium, May 25, 2010 in New Orleans.
  • Pitfalls of Class Action Notice and Claims Administration presented at Practicing Law Institute’s Class Action Litigation Conference, July 9, 2014 in New York City.
  • The Other Data Breach Cases: Medical Records Cases and Cases on Behalf of Banks and Others presented at HarrisMartin’s Data Breach Litigation Conference, March 25, 2015 in San Diego.
  • AAJ Education’s Plaintiff-Only Hot Topics and Trends in Litigation Seminar, May 27, 2015 in Minneapolis.
  • Class Actions: Where to Begin panel at HB Litigation Conferences' Mass Tort Med School + Class Actions, March 17, 2017 in Orlando.
  • Presented at Practising Law Institute's Class Action Litigation 2017 program, June 21, 2017 in New York City.

Professional Associations

Ms. Riebel was elected as an officer of the National Association of Shareholder and Consumer Attorneys (NASCAT) in 2007. She is also a member of the Federal Bar Association.

Civic Associations

  • Page Education Fund Board of Advisors
  • Project for Pride in Living Board of Directors


  • Boston University School of Law, 1991

Bar Admissions

  • 1991, Minnesota

Court Admissions

  • Minnesota
  • U.S. District Court, District of Minnesota
  • Third Circuit Court of Appeals
  • Eighth Circuit Court of Appeals