People
Mark Jensen is Co-Chair of the firm-wide Special Matters and Government Investigations practice group and Managing Partner of King & Spalding’s Washington, D.C. office. He specializes in high-profile investigations, white-collar litigation for companies and individuals, regulatory enforcement actions, internal reviews and compliance counseling. Mark’s practice has been nationally acclaimed, and he has been widely recognized for the positive results he obtains for an array of clients in criminal and civil cases, including governmental investigations, prosecutions and False Claims Act civil litigation. Law360 has described him as “one of the most sought-after corporate defenders in the country” and the Legal 500 as “an extremely accomplished lawyer.” Clients selected him for the prestigious BTI Client Service All-Stars Award, commending his judgment, “practical approach” and knowing “what to fight for.” He also has been ranked by The Best Lawyers in America 2025 and named a 2025 Lawdragon 500 Leading Litigator in America.
Mark defends leading companies and senior executives in litigation in federal and state courts, as well as in prosecutions and investigations by U.S. Attorneys, multiple divisions of the U.S. Department of Justice, the Securities and Exchange Commission, Food and Drug Administration, Environmental Protection Agency, National Oceanic and Atmospheric Administration, and Congress.
Mark’s litigation experience includes criminal and civil issues relating to pharmaceuticals, biotechnology, laboratory testing and medical devices; Foreign Corrupt Practices Act matters; tax and accounting-related fraud; environmental and wildlife prosecutions; and federal contracting and procurement fraud.
In addition to his current role as Managing Partner, Mark has served in numerous other firm leadership roles. Elected by his partners to the firm’s managing Policy Committee, he also has served on the firm-wide Lateral Partner Committee and the Performance Management and Compensation Committee. He also served as Lateral Partner Hiring Lead for the firm-wide Government Matters Practice Group, and previously was the Hiring Partner and Deputy Managing Partner for the D.C. office.
Legal 500 U.S. recommended Mark for white-collar criminal defense in 2024 and previous years, describing him as “brilliant and creative” with “an excellent track record.” Benchmark Litigation recognized him as a “Litigation Star” in its 2023 and previous editions. LMG Life Sciences named Mark a Life Sciences Star for White Collar/Government Investigations in its 2023 and previous editions, including shortlisting him multiple times as one of six lawyers nationwide for Government Investigations Attorney of the Year.
J.D., Harvard University, cum laude
B.A., Indiana University, summa cum laude, Phi Beta Kappa
District of Columbia
U.S. Court of Appeals for the Seventh Circuit
U.S. District Court for the Northern District of Illinois
U.S. District Court for the Southern District of Indiana
Law Clerk, Hon. Sarah Evans Barker, U.S. District Court for the Southern District of Indiana
September 19, 2024
King & Spalding Earns Multiple Rankings in LMG Life Sciences 2024 Guide
June 12, 2024
King & Spalding Earns Top-Tier Rankings in Legal 500 United States 2024 Guide
October 10, 2023
Benchmark Litigation Again Recognizes King & Spalding as a Leading Litigation Firm
Represented a variety of life science and health care companies, as well as individual employees, officers, consultants and medical professionals, in criminal and civil litigation by multiple U.S. Attorneys Offices, DOJ, HHS-OIG, qui tam Relators, state attorneys general and national Medicaid fraud control units, regarding alleged “off-label” promotion, unlawful inducements and other sales, marketing, pricing and development activities. Successfully represented a variety of clients in these investigations, including prevailing on motions to dismiss False Claims Act lawsuits in federal district court and resolving successfully the largest U.S. False Claims Act matter involving a medical device and kickback allegations.
Represented Janssen Pharmaceuticals, Johnson & Johnson and related companies in a 2013 global resolution of multiple DOJ investigations, including the negotiation and settlement of False Claims Act; Food, Drug & Cosmetic Act; and related allegations. The False Claims Act component of the resolution included seven qui tam complaints venued in the E.D.Pa., D.Mass. and N.D.Ca. Also led the related resolution of administrative claims by HHS-OIG through the company’s Corporate Integrity Agreement. In parallel state litigation, led the resolution of multi-state and individual state consumer protection claims and lawsuits, as well as state claims alleged by Medicaid Fraud Control Units and similar attorneys general and state representatives.
Represented Coach Joe Paterno and his Estate and Family in matters pertaining to the NCAA and Pennsylvania State University.
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December 12, 2023
General Counsel’s Decision Tree for Internal Investigations for the Life Sciences Industry
December 8, 2023
General Counsel’s Decision Tree for Internal Investigations for the Food and Beverage Industry
November 9, 2023
General Counsel’s Decision Tree for Internal Investigations for the Healthcare Industry
September 19, 2024
King & Spalding Earns Multiple Rankings in LMG Life Sciences 2024 Guide
June 12, 2024
King & Spalding Earns Top-Tier Rankings in Legal 500 United States 2024 Guide
October 10, 2023
Benchmark Litigation Again Recognizes King & Spalding as a Leading Litigation Firm
Represented a variety of life science and health care companies, as well as individual employees, officers, consultants and medical professionals, in criminal and civil litigation by multiple U.S. Attorneys Offices, DOJ, HHS-OIG, qui tam Relators, state attorneys general and national Medicaid fraud control units, regarding alleged “off-label” promotion, unlawful inducements and other sales, marketing, pricing and development activities. Successfully represented a variety of clients in these investigations, including prevailing on motions to dismiss False Claims Act lawsuits in federal district court and resolving successfully the largest U.S. False Claims Act matter involving a medical device and kickback allegations.
Represented Janssen Pharmaceuticals, Johnson & Johnson and related companies in a 2013 global resolution of multiple DOJ investigations, including the negotiation and settlement of False Claims Act; Food, Drug & Cosmetic Act; and related allegations. The False Claims Act component of the resolution included seven qui tam complaints venued in the E.D.Pa., D.Mass. and N.D.Ca. Also led the related resolution of administrative claims by HHS-OIG through the company’s Corporate Integrity Agreement. In parallel state litigation, led the resolution of multi-state and individual state consumer protection claims and lawsuits, as well as state claims alleged by Medicaid Fraud Control Units and similar attorneys general and state representatives.
Represented Coach Joe Paterno and his Estate and Family in matters pertaining to the NCAA and Pennsylvania State University.
See more
December 12, 2023
General Counsel’s Decision Tree for Internal Investigations for the Life Sciences Industry
December 8, 2023
General Counsel’s Decision Tree for Internal Investigations for the Food and Beverage Industry
November 9, 2023
General Counsel’s Decision Tree for Internal Investigations for the Healthcare Industry
September 19, 2024
King & Spalding Earns Multiple Rankings in LMG Life Sciences 2024 Guide
June 12, 2024
King & Spalding Earns Top-Tier Rankings in Legal 500 United States 2024 Guide
October 10, 2023
Benchmark Litigation Again Recognizes King & Spalding as a Leading Litigation Firm
J.D., Harvard University, cum laude
B.A., Indiana University, summa cum laude, Phi Beta Kappa
District of Columbia
U.S. Court of Appeals for the Seventh Circuit
U.S. District Court for the Northern District of Illinois
U.S. District Court for the Southern District of Indiana
Law Clerk, Hon. Sarah Evans Barker, U.S. District Court for the Southern District of Indiana