Claire E.Castles


Los Angeles +

Claire Castles advises clients on complex health care and life science regulatory compliance issues in transactions, investigations, and litigation matters, including issues that are international in scope, relate to significant regulatory enforcement, and present potential reputational concerns.

Claire helps clients implement response strategies for novel and emerging public health threats, including COVID-19. She assists clients in regulatory waiver strategies and impact on corporate practice of medicine, HIPAA/HITECH, and other state and federal regulations and guidance. Claire assisted clients in obtaining first-of-its-kind "hospital without walls" waivers from CMS (Centers for Medicare & Medicaid Services). She also advises clients on health reform strategies that include assistance with CMMI (Center for Medicare and Medicaid Innovation) pilot program participation and value-based and risk-based payment arrangements. Claire also assists clients in assessing hospital closure issues and distressed hospital strategies.

Claire works with clients to implement strategic practices advancing regulatory compliance related to Medicare and Medicaid, payment reform, graduate medical education programs, clinical trials, 340B and Medicaid Drug Rebate programs, and drug and device coverage and reimbursement. She advises clients in operational and administrative responses to licensing, survey, and audit findings, including immediate jeopardy, health privacy allegations, CMS suspension and termination, and state and federal Office of Inspector General investigations and disclosures. Claire also assists with repayments and remediation strategies to private payors and state and federal agencies, including the Medicare and Medicaid program.

Claire is a voting member of the National Native American Bar Association and Fellow of the American Bar Foundation.


  • California Hospital Association wins summary judgment in labor law and health care caseJones Day secured a major win for the California Hospital Association (CHA) in a matter that has significant ramifications for labor law and the health care industry.
  • Adventist Health maintains access to emergency services for Montebello community through chapter 11 saleJones Day advised Adventist Health in connection with its acquisition of certain assets of Beverly Community Hospital Association through Chapter 11 bankruptcy proceedings, which closed on September 6, 2023 and allowed Adventist Health to advance ongoing access to necessary emergency department services for the Montebello community in East Los Angeles.
  • KKR acquires IVI-RMA GlobalJones Day acted as U.S. counsel in the €3 billion acquisition of IVI-RMA, a group specialized in assisted reproduction techniques.
  • Ascension enters into strategic laboratory collaboration with LabcorpJones Day advised Ascension with respect to its strategic alliance with Labcorp whereby Labcorp will manage Ascension’s hospital-based laboratories in 10 states and purchase the assets of the health system’s outreach laboratory business.
  • Misonix merges with BioventusJones Day represented Misonix, Inc. (Nasdaq: MSON) in its acquisition by Bioventus Inc. (Nasdaq: BVS).
  • PWNHealth and Home Access Health Corporation sold to Everlywell, forming Everly HealthJones Day advised PWNHealth LLC and Home Access Health Corporation in its sale to Everlywell, a leading digital health company, and forming Everly Health.
  • Digital health company expands telehealth programming in response to the COVID-19 public health crisisJones Day represented a digital health company in the expansion of their telehealth programming in response to the COVID-19 public health crisis.
  • Arsenal Capital Partners acquires HistoGeneX and Caprion BiosciencesJones Day advised Arsenal Capital Partners on major investments in HistoGeneX and Caprion Biosciences and the subsequent combination of the two businesses.
  • Ambry Genetics sold to joint venture formed by Konica Minolta and Innovation Network for up to $1.0 billionJones Day advised Ambry Genetics Corporation, a leading genetic testing corporation, in its sale to a newly formed joint venture between Konica Minolta, Inc. and Innovation Network Corporation of Japan for up to $1.0 billion (including earnouts).
  • Health care management company conducts internal investigation relating to alleged overpayment of federal health care fundsJones Day represented a privately-owned health care management company in an internal investigation relating to alleged overpayment of federal health care funds.
  • Health care management company reviews compliance with Medicare regulationsJones Day provides ongoing counseling, training, and advice to a health care management company regarding compliance with federal and state health care regulations.
  • Major academic medical center forms Medicare accountable care organizationJones Day represented a major academic medical center in connection with the formation of a Medicare accountable care organization ("ACO"), including hundreds of providers in a distributive, shared governance model.
  • Health care services company successfully resolves FCA retaliation suitJones Day represented a health care services company in a suit brought by a former employee asserting claims of retaliation for allegedly investigating and reporting violations of the False Claims Act by the company.
  • California hospital obtains dismissal of qui tam actionJones Day successfully defended a California healthcare district and hospital against an investigation conducted by the U.S. Attorney's Office for the Northern District of California, the Department of Justice Civil Frauds Section, the California Office of the Attorney General, and the Health and Human Services/Office of Inspector General.
  • Abbott purchases option to acquire Cephea Valve TechnologiesJones Day advised Abbott Laboratories in the providing of capital and securing of an option to purchase Cephea Valve Technologies, a private company developing a catheter-based mitral valve replacement therapy.
  • Community hospital seeks compliance advice on graduate medical education programJones Day assisted a community hospital in developing a compliance strategy for its residency program relating to its graduate medical education accreditation, including coordination and discussions with Centers for Medicare and Medicaid Services as to its administration of graduate medical education slots distributed as part of federal health care reform.
  • Ensign Group completes public offering of Common StockJones Day advised The Ensign Group, Inc., the parent company of the Ensign (TM) group of skilled nursing, rehabilitative care services, assisted living, home health, home care, hospice care and urgent care companies, in connection with its public offering of 2,733,617 shares of Common Stock.
  • Dignity Health wins dismissal of 32 casesJones Day secured the dismissal of 32 separate cases brought against Dignity Health's St. Bernardine hospital over spinal implants.
  • Ambulatory surgery center enters into buyout with partners and converts to outpatient departmentJones Day represented an academic medical center in the buyout of its joint venture partners in an ambulatory surgery center.
  • Celtic Healthcare and Allegheny Health Network complete joint venture to combine home health and hospice assets in western PennsylvaniaJones Day advised Celtic Healthcare, Inc., a majority owned subsidiary of The Graham Holdings Company and an innovative leader in the delivery of home health care in Pennsylvania and Maryland, in the formation of a joint venture with Allegheny Health Network that will combine each organization's home health and hospice assets in the western Pennsylvania region to create a new, fully integrated and industry-leading provider of post-acute care services operating under the AHN brand and managed by Celtic's support service and leadership team.
    • September 14, 2017
      Trends in Clinical Trials, Regulatory Risks and Strategies for Commercialization, Fourth Annual ABA Life Sciences Legal Summitt
    • April 24, 2017
      Planning for MACRA, Health Reform, and Reimbursement Changes
    • July 26, 2016
      CMS 60-Day Rule (Intermediate), AHLA Distance Learning Series
    • May 21, 2014
      Responding to Licensing and Certification Deficiencies, California Hospital Association
    • April 17, 2014
      Increased Focus on Enforcement in Clinical Research - Lessons from Recent Cases, San Diego Regulatory Affairs Network
    • February 2013
      Healthcare Data Security: Practical Tips For Managing Risk From Legal and Enforcement Perspective, ABA Emerging Issues Conference
    • October 17, 2012
      Jones Day / Navigant 16th Annual Health Care Compliance Forum
    • June 18, 2012
      Lessons Learned: What Providers and ACOs Looking to Participate in 2013 Should Anticipate, AHLA Webinar
    • March 1, 2012
      AHLA Healthcare Fraud and Abuse Bootcamp Webinar Series, Part III: The Federal Anti-Kickback Law: An Overview, Recent Enforcement Trends and Impact of Healthcare Reform
    • October 20, 2011
      Payment Reform and Its Implications for Your Health System, 15th Annual Health Care Compliance Forum
    • 2011
      Health Reform - Understanding the Law, University of California Compliance & Audit Symposium
    • 2010
      Understanding POLST Forms, Fresno County Bar Association
    • 2009, 2008, 2007, 2006
      Annual Health Care Fraud and Abuse Education Updates, American Association of Professional Coders, Fresno Chapter
    • 2009
      Medical Identity Theft and Red Flag Rules, Central Valley of California