Dennis Diaz is a healthcare regulatory and transactional lawyer. Known for his results-oriented approach, Dennis is sought out to handle disputes and defend enforcement actions brought by healthcare regulatory agencies; lead internal client reviews, investigations, and audits to assess healthcare regulatory risk and implement corrective actions; and structure provider and hospital-physician transactions. Healthcare providers often call on him to solve difficult regulatory problems that are not mainstream or 'cookie-cutter,' saying that Dennis is a "terrific practitioner" who is "knowledgeable, practical, and fully understands the healthcare regulatory environment." (Chambers client quotes, 2019 and 2016.)
Best Lawyers of America named Dennis Los Angeles' Administrative and Regulatory Lawyer of the Year in 2017 for his successful dealings with healthcare regulatory agencies, and he has been recognized consistently over the years by Chambers and Best Lawyers of America as one of California's leading healthcare lawyers. Dennis has taught courses in Health Law at the University of Southern California Gould School of Law and at Loyola Law School in Los Angeles.
Dennis has represented large multi-hospital provider organizations, independent hospitals, medical groups, ambulatory surgery centers, accountable care organizations, clinically integrated networks, and other healthcare organizations. He also has served as principal outside counsel and compliance counsel for community hospitals and medical groups. His depth of knowledge extends to issues of healthcare fraud and abuse, anti-kickback, Stark, false claims, civil money penalties, third-party payor reimbursement (including Medicare and Medicaid), billing and coding, licensing, certification, accreditation, provider operations, and compliance.
Negotiations with healthcare regulatory agencies
Healthcare business transactions
Admitted to Practice
J.D., University of California, Los Angeles, School of Law
B.A., University of California, Santa Barbara, with honors
Memberships & Affiliations
- American Health Lawyers Association
- Named one of "America's Leading Lawyers for Business" in Health Care (California) by Chambers USA, 2010-2019
- Named one of the country's 12 "Outstanding Hospital Lawyers" by Nightingale's Healthcare News, 2007
- Selected by Best Lawyers as Los Angeles' "Lawyer of the Year" in Administrative/Regulatory Law, 2017
- Named one of the "Best Lawyers in America" in Health Care Law by Best Lawyers, 2010-present
- Selected to, "Top Rated Lawyers Guide to Health Care Law," Corporate Counsel
- Highest rating (AV) by peers – Martindale-Hubbell Legal Rating Service
- Adjunct Professor of Law, Health Law, University of Southern California Gould School of Law
- Adjunct Professor of Law, Health Law, Loyola University School of Law
- Lecturer, Health Care Law for Managers and Entrepreneurs, University of California, Irvine - Executive MBA Program
- Partner, Sonnenschein Nath & Rosenthal LLP
- Staff Counsel, Office of General Counsel, U.S. Department of Health and Human Services, Washington, D.C.