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Crowell & Moring LLP

Work +1 202 624 2500
Fax +1 202 628 5116
Crowell & Moring LLP, William O’Neill, Washington DC, USA

William O’Neill

Work +1 202.624.2950
Crowell & Moring LLP


William C. O'Neill is a partner and co-chair of the firm's Insurance/Reinsurance Group. His practice focuses primarily on arbitrations and litigations on behalf of insurers, reinsurers, and health care companies. Bill has been involved in hundreds of disputes involving issues in life, health, and property/casualty insurance and reinsurance issues. He has represented clients in disputes involving yearly renewable term reinsurance premiums, environmental and asbestos reinsurance allocations, maximum any one life warranties, extra-contractual obligations, fronting arrangements, sunset and commutation clauses, actuarial and agency issues, vanishing premium life insurance policies, cedent insolvencies, long-term care premiums, follow the fortunes and follow the settlements, late notice, retention warranties, underwriting and claims handling practices, 9/11 issues, fraud, offset, misrepresentations, recovery of declaratory judgment expenses, and allegations of misconduct by brokers, managing general underwriters, and third-party administrators. These disputes center on many types of underlying exposures and business, including, variable annuities, individual life, health care, workers' compensation, long-term care, disability income, accident and health, asbestos, environmental, and construction defect exposures. In addition to his dispute work, Bill counsels clients regarding business, strategy, and regulatory matters. He works closely with the firm's Health Care and Litigation practices and has worked on insurance-related issues with our International Trade, Intellectual Property, Corporate, and Antitrust practices. Bill is recognized as a top insurance and reinsurance attorney in Chambers USA (2014 and 2015), as well as Euromoney's Guide to the World's Leading Insurance & Reinsurance Attorneys (2008 thru present) and the International Who's Who of Insurance and Reinsurance Lawyers. He is a frequent speaker on reinsurance issues and has served on the faculty at numerous training seminars for reinsurance arbitrators. He is a member of the AIDA Reinsurance and Insurance Arbitration Society (ARIAS-US) education committee, a former chair of the Excess, Surplus Lines and Reinsurance Committee of the Torts and Insurance Practice Section of the American Bar Association, and a member of the American Health Lawyers Association.

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