Diane Ung is a partner and health care lawyer with Foley & Lardner LLP in the Los Angeles office. Diane focuses her practice on federal and state health care legislation and payment issues arising under government programs such as Medicare and Medicaid. Her practice includes regulatory, legislative, health care, and business matters for public agency clients and non-profit hospitals and clinics. Diane has specific experience in structuring Medicaid financing for safety net providers in the context of disproportionate share hospital payment programs, federal Medicaid demonstrations authorized under Section 1115 of the Social Security Act, and Medicaid managed care. Diane is a senior member of the firm's Health Care Practice Group.

Diane represents county health and behavioral health departments, county, and local public agency managed care organizations, public hospitals and health care systems, and various large publicly operated teaching hospitals. She has helped clients evaluate and develop Medicaid demonstration and waiver projects that implement innovative programs for Medicaid beneficiaries. Diane has drafted Medicaid legislation, including statutes involving disproportionate share hospital (DSH) payment adjustment systems, and has advised clients on regulatory compliance, including Medicaid program audits of supplemental payments conducted by the DHHS Office of the Inspector General (OIG). She has counseled clients in connection with strategic alliances, and the restructuring of public health agencies and the evaluation of public/private partnerships, including the transfer of a public hospital to a nonprofit entity. Diane also has advised public and not-for-profit clients on matters involving federally qualified health centers (FQHC), the 340B drug pricing program, and on behavioral health integration.

Prior to beginning her legal career, Diane was a facility health planner and health services researcher for a major health maintenance organization.

Recognition and Recent Publications

  • Chambers USA: America's Leading Lawyers for Business, Healthcare (2021-2023)
  • Southern California Super Lawyers® since 2014
  • The Best Lawyers in America© since 2013, Health Care Law
  • White Paper: Voluntary Behavioral Health Integration in Medi-Cal (co-authored with Anil Shankar), for California Health Care Foundation, October 2019.


  • Loyola Law School, Los Angeles (JD, 1993)
    • Order of the Coif
  • University of California, Los Angeles, School of Public Health (MSPH, 1987), Health Planning and Policy Analysis
  • Pomona College (BA, 1985), Biology

Professional Memberships

  • Member, American Health Lawyers Association
  • Member, California Society for Healthcare Attorneys
  • Member, Los Angeles County Bar Association
    • Previously served as chair of the Healthcare Law Section
  • Previously served on the board of directors of the Women in Health Administration of Southern California, serving as its president in 2007 and 2008


  • California (1993)
  • District of Columbia (1996)