Mary Powers Antoine has more than three decades of legal experience in the healthcare industry with a previous career as a registered nurse to deliver personalized legal advice with a real world perspective.  She represents managed care plans, hospitals and health facilities as well as physicians' groups on a wide range of regulatory, contracting and licensing issues.  She advises medical staffs on peer review investigations, hearings and other disciplinary actions, bylaws, rules and regulations, Joint Commission compliance and compliance with state and federal laws, and patient care issues.  

Mary has developed an in-depth understanding of the operational and business issues the healthcare industry faces.  She uses her expertise to guide clients on the full range of state and federal regulatory and accreditation issues from Medicare and Medi-Cal, The Joint Commission and the California Knox-Keene Health Care Service Plan Act, to HIPAA and EMTALA.  She has represented clients in matters involving the Department of Managed Health Care, the Joint Commission, NCQA and the Centers for Medicare & Medicaid Services.

Mary's experience representing clients from different sectors of the industry provides her with a strategic understanding of the business issues they face.  She offers her clients pro-active and practical legal solutions to further their business success.

Mary has been chosen for individual recognition in California Healthcare by Chambers and Partners and is AV Preeminent® Peer Review Rated by Martindale-Hubbell.  Additionally, she has been selected to the Northern California Super Lawyers list in the area of Healthcare.  She was also the first woman to serve as Nossaman's assistant managing partner.


Speaking Engagements



Community & Professional

Past President, The American Association of Nurse Attorneys

Past Instructor in Managed Care Law and Healthcare Law, University of California, Davis

Board of Trustees, Chair of Medical Policy Committee, Sutter Health Sacramento Sierra Region (2000-2009)

American Bar Association

California Society of Health Care Attorneys

American Health Lawyers Association

Sacramento County Bar Association, Health Law Section


Honors & Recognitions

Chosen for individual recognition for Healthcare in California by Chambers USA, 2014-2018

Selected to the Northern California Super Lawyers list, 2010-2014, 2016-2019

Recognized on the Top 100 Women Lawyers list by the Daily Journal, 2015

AV Preeminent® Peer Review Rated by Martindale-Hubbell



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