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Energy, Contract, Regulatory, & Administrative Law

David S. Rosenzweig is Executive Partner at Keegan Werlin LLP and Chair of the Firm’s Energy Siting & Permitting Practice, representing clients before state regulatory agencies, local permitting authorities and the Massachusetts courts. He advises a wide array of electric and gas companies, energy project developers and end users on issues concerning the siting, permitting and licensing of energy facilities, rates, planning, energy procurement and transmission arrangements.

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David S. Rosenzweig

Boston Office

Phone: 617-951-1400
Fax: 617-951-1354

● Administrative Law
● Energy Law
● Regulatory Law
● Contract Law

Bar Admissions
U.S. Court of Appeals D.C. Circuit
U.S. Court of Appeals First Circuit
U.S. District Court District of MA

U.S. Supreme Court


New Hampshire

Mr. Rosenzweig’s siting expertise includes: electric transmission lines (underground, aboveground and underwater); natural gas, oil and coal-fired electric generating facilities; interstate and intrastate natural gas pipelines; natural gas storage facilities; and solar, wind and battery storage renewable energy facilities. He represented the region's first large-scale, offshore wind power project in obtaining its state and local permits, licenses and siting approvals for energy infrastructure facilities from the Energy Facilities Siting Board, the Executive Office of Environmental Affairs pursuant to the Massachusetts Environmental Policy Act, the Department of Environmental Protection and various other state and local agencies, boards and governmental authorities.

He has also represented utility companies and project developers in judicial proceedings in state and federal courts, including the Massachusetts Supreme Judicial Court, regarding challenges to permits and approvals initiated by project opponents.


Mr. Rosenzweig has also represented the region's electric and natural gas distribution companies on all regulatory matters before the Massachusetts Department of Public Utilities. He has negotiated electric and gas supply agreements for large institutional energy users and power sale agreements for wholesale electric generators. He has advised clients in restructurings, buydowns and buyouts of power sale agreements between competitive wholesale generators and electric distribution companies. In addition, he has counseled clients on transmission, power delivery and project interconnection issues concerning the New England Power Pool and the New England Independent System Operator. Mr. Rosenzweig has also performed regulatory and permitting due diligence reviews for asset acquisitions of natural gas, oil and coal-fired electric generating facilities.


Before joining the firm in 1990, Mr. Rosenzweig worked at Boston Edison Company for seven years in a variety of legal, financial, rate and planning areas.

Image by American Public Power Association


Suffolk University Law School, Boston, Massachusetts, J.D., cum laude, 1988

Rensselaer Polytechnic Institute, Troy, New York, M.B.A., 1982

Rensselaer Polytechnic Institute, Troy, New York, B.S. Management, 1981


"The Best Lawyers In America" 2007 - 2022


Boston Bar Association

Massachusetts Bar Association

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