LAWYER PROFILE
T. J. Sullivan

T. J. Sullivan

USA 2026

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Ranked in 1 practice area

About

Provided by Potomac Law Group

USA

Practice Areas

Corporate and Transactional

Health Care

Joint Ventures and Strategic Alliances

Nonprofit and Tax-Exempt Organizations

Tax-Exempt Organization Governance and Compliance

Taxation

Career

T.J. Sullivan is a Partner in PLG's Health Care Practice, advising tax-exempt organizations on complex regulatory and transactional issues. In more than 30 years working on tax matters, Mr. Sullivan has distinguished himself as a trusted partner to tax-exempt entities, including hospitals, health maintenance organizations (HMOs), clinics, and integrated health systems. A former Special Assistant for Health Care at the Internal Revenue Service, Mr. Sullivan brings a meticulous approach and an insider’s perspective on taxation to every client matter.

Mr. Sullivan advises tax-exempt entities and associations—particularly in the health care space—on tax compliance, reporting, and governance matters. He counsels clients regarding mergers, acquisitions, and sale transactions, and advises on affiliations, joint ventures, and executive compensation and benefits matters. When necessary, he represents exempt organizations in the U.S. Tax Court.

Professional Memberships

-American Health Law Association, Fellow

-Board of Directors (1995-2001)

-Tax Issues Program Committee (Chair 2000-06)

-American Bar Association

-Tax Section

-Health Care Subcommittee of the Committee on Exempt Organizations (former Co-Chair)

-The Exempt Organization Tax Review—Editorial Advisory Board

Work Highlights

-Obtained a Declaratory Judgment in U.S. Tax Court for the Marshfield Clinic Health System, Inc., the parent of an integrated health care delivery system.

-Defended IRS examinations involving executive compensation and benefits and other potential excess benefits transactions issues in several regions.

-Obtained a Declaratory Judgment in U.S. Tax Court for the John Gabriel Ryan Association, a health system subsidiary that operated several joint ventures.

Chambers Review

Provided by Chambers

Chambers Guide to the USA

Healthcare - District of Columbia

Senior Statesperson
Senior Statespeople

Individual Editorial

TJ Sullivan is held in high regard for his longstanding expertise at the intersection of tax and healthcare mandates.

Ranked Individuals at Potomac Law Group (7)

District of Columbia

Maine

Michigan

USA - Nationwide

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