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    John H. O'Neill, Jr.

    John H. O'Neill, Jr.
    Retired Partner

    T: +1.202.663.8148 F: +1.202.663.8007
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    John O’Neill, a retired partner in Pillsbury’s Energy practice concentrates on energy, environmental, and public utility law. Mr. O’Neill represents electric utilities and companies in the nuclear industry in major commercial transactions, regulatory proceedings, and dispute resolution matters.

    Commercial Transactions

    Mr. O’Neill has an established commercial law practice and extensive experience in domestic and international transactions involving the acquisition and sale of power plants, major plant components, nuclear fuel, and services. He has represented both sellers and buyers in transactions involving the acquisition of nuclear power plants and was lead counsel in the acquisition of the Seabrook, Duane Arnold, and Point Beach nuclear plants. He has represented clients in investment in and financing of new reactor projects. He has represented foreign governments and international clients on major nuclear procurements and nuclear regulatory matters. He has advised foreign governments on establishing a commercial nuclear program and one foreign government on privatization of its nuclear program. Mr. O’Neill also advised a US national laboratory on fusion energy commercialization.

    Administrative Proceedings

    Mr. O'Neill's representation of electric utilities and other clients before administrative agencies, such as the US Nuclear Regulatory Commission (NRC), the US Department of Energy (DOE), and various state regulatory bodies, generally involves licensing, rulemaking, enforcement actions, or utility rate proceedings involving power plants. He has served as lead licensing counsel in obtaining NRC operating licenses, major license amendments, license transfers, and enforcement actions. He was lead partner representing a number of new reactor projects before the NRC, including a contested hearing on environmental issues for the first new nuclear reactor to be located at a “greenfield” site.

    Dispute Resolution

    Mr. O'Neill's practice focuses specifically on dispute resolution in federal and state courts and before domestic and foreign arbitral tribunals. He has served as lead counsel in a jury trial in federal court involving defective nuclear plant components, cases in the Court of Federal Claims for overcharges by the DOE for nuclear fuel services, and a number of arbitrations before the International Chamber of Commerce involving failures of nuclear plant components. He has successfully resolved a number of these disputes, including two with the US government, in mediations.

    Education and Nuclear Energy Experience

    After graduation from the US Naval Academy with distinction in 1968, Mr. O'Neill completed graduate work in nuclear engineering as part of the US Navy nuclear power training program, designed and supervised by Admiral Hyman G. Rickover. Prior to practicing law, Mr. O'Neill was an officer in the US Navy serving on nuclear submarines. He was licensed by the Atomic Energy Commission to supervise the operation and maintenance of naval nuclear propulsion power plants.


    Mr. O’Neill served as a member of the Firm's Board on several occasions during his 40 years with the Firm. He had a major role in the integration of Shaw Pittman Potts & Trowbridge with Pillsbury Winthrop after the merger of the two firms in 2005 and formed the new Regulatory Department of the combined Firms. He served as one of three department heads of the Firm for 10 years. He headed up the Firm’s internationally acclaimed Energy Section for many years. Recently he has worked to develop leadership training and coaching for the Firm’s lawyers and has taken the lead in conducting leadership seminars.

    Honors & Awards
    • Chambers USA, Energy: Nuclear-Regulatory—National (2005-2016)
    • Chambers Global, Energy: Nuclear-Regulatory & Litigation—USA (2007-2015)
    • Legal 500 US, Energy—Regulatory (2015)
    • Best of the Best USA, Energy & Natural Resources, Euromoney/Legal Media Group (2008, 2010)
    • Guide to the World's Leading Energy and Natural Resources Lawyers, Euromoney/Legal Media Group (2007)


    International Bar Association; International Nuclear Law Association; U.S. Naval Academy Foundation, Trustee


    U.S. Supreme Court, U.S. Courts of Appeals for the Federal and Third Circuits, U.S. District Court for the District of Columbia, Court of Appeals of Maryland, District of Columbia Court of Appeals

    District of Columbia
    State of Maryland
    J.D., Yale Law School, 1976
    United States Navy Nuclear Power School, 1969
    B.S., United States Naval Academy, 1968
    with distinction

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