Stephen M. Sullivan


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Stephen Sullivan regularly represents health care organizations in a wide variety of regulatory, enforcement, and business matters. Stephen commonly advises and defends clients on matters involving state and federal false claims laws, anti-kickback laws, Stark laws, Medicare and Medicaid reimbursement laws, state and federal privacy laws, and laws regulating managed care organizations. Stephen has extensive experience leading internal investigations and managing government disclosures of alleged misconduct for clients in the health care industry.

Stephen also advises health care companies on complex strategic business challenges and opportunities, as well as a variety of business transactions, including mergers and acquisitions. While Stephen’s work crosses all sectors of the health care industry, he has extensive experience counseling clients in managed care. Stephen advises managed care organizations doing business with federal health care programs, including Medicare Advantage Plans, Prescription Drug Plans, and Medicaid Plans, on matters involving sales and marketing practices, risk adjustment reimbursement, and other areas affecting such organizations.

Honors & Awards

  • Recommended by The Legal 500 US Healthcare: Health Insurers (2019)
  • Named to Benchmark Litigation's 40 & Under Hot List in Healthcare (2018-2022)


Bar Admissions

  • California


  • Southwestern Law School, J.D.: summa cum laude; Southwestern University Law Review (2005-06); Moot Court Honors Program
  • University of California at Santa Barbara, B.A., English and Dramatic Arts: highest honors

Professional Activities


  • Honorable Ron Parraguirre, Nevada State Supreme Court


  • Honorable S. James Otero, U.S. District Court, Central District of California


  • “Critical Questions To Consider About The ACA,” Law360 (October 30, 2013) (co-authored with David Deaton and Michael Maddigan)
  • “Trepidation Over Health Insurance Exchanges,” The Daily Journal (June 12, 2013) (co-authored with David Deaton)
  • “The Affordable Care Act, Public Expectations, and the Road to Litigation: An Issue Spotter for Insurers and Risk-Bearing Providers,” AHLA Connections (Volume 17 Issue 2, Feb. 2013) (co-authored David Deaton)
  • “Navigating the Rising Legal Waters in Managed Care,” American Health Lawyers Association’s Fraud & Abuse newsletter (Volume 1, Issue 4, Dec. 2012) (co-authored with David Deaton and Patricia Kuo)


  • “Key Trends in Risk Adjustment: Standards, Developments & Risks in Medicare & Beyond,” Blue National Summit (April 2015)
  • “Risk Factors in Risk Adjustment: Key Standards, Developments, and Risks in Medicare Advantage,” American Health Lawyers Association, Payers, Plans, and Managed Care Practice Group (September 2014)
  • “Compliance & Enforcement Issues in Managed Care,” Blue National Summit (May 2014)
  • “Expanded Liability for Payors under the False Claims Act: Escalating Risk and Response for Managed Care Organizations, American Bar Association, Emerging Issues in Healthcare Law” (March 2014)
  • “Expanded Liability for Payors under the False Claims Act: Escalating Risk and Response for Managed Care Organizations,” ABA Health Law Section's Conference on Emerging Issues in Healthcare Law (February 26, 2014)
  • “Data Analytics and Compliance Effectiveness,” Health Care Compliance Association South Atlantic Regional Conference (February 7, 2014)
  • “Risk Adjustment: Key Standards, Developments, and Risks in Medicare Advantage and Beyond,” American Health Lawyers Association (June 26, 2013)
  • “Managed Care Compliance,” Health Care Compliance Association’s Puerto Rico Regional Conference (May 3, 2013)


  • American Health Lawyers Association
  • Led an investigation of a prominent managed care company’s compliance with the federal Anti-Kickback Statute and Medicare Advantage regulations
  • Defending a national managed care organization in a qui tam action concerning allegations of False Claims Act liability attributable to the risk adjustment practices of an in-home health assessment vendor contracted by our client
  • Obtained dismissal with prejudice and without leave to amend on behalf of one of the nation’s largest health insurance companies in a qui tam action alleging claims under the federal and California False Claims statutes arising out of the submission of Medicare and Medicaid claims
  • Obtained dismissal with prejudice on several claims and limited the remaining claims on behalf of one of the nation’s largest health insurance companies in a qui tam action alleging that doctors falsely diagnosed many patients with illnesses or illness-related complications, which resulted in the submission of false claims to Medicare for reimbursement
  • Representing a national managed care organization in connection with state and federal investigations into individual health insurance cancellation practices