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John Guernsey

Of Counsel

John Guernsey represents clients in complex commercial litigation and fiduciary litigation, with a strong focus on restrictive covenant and trade secret matters as well as trust and estate matters. John has also served as lead counsel on intellectual property litigation, products liability and complex torts, and employment litigation.

John focuses his practice in federal and state courts in Pennsylvania and New Jersey, but he has appeared in courts from the Virgin Islands to Texas in representation of clients.

Education

J.D., Harvard Law School, Cambridge, Massachusetts
B.S., with distinction, United States Military Academy at West Point

Recognitions

Selected as a Leading Lawyer for General Commercial Litigation in Chambers USA, The Client’s Guide to America’s Leading Lawyers for Business (2010–2024)

*This award is conferred by Chambers and Partners. A description of the selection methodology can be found at https://chambers.com/about-us/methodology. No aspect of this advertisement has been approved by the Supreme Court of New Jersey.

 

Listed as Best Lawyers in America Philadelphia “Lawyer of the Year” for Litigation – Trusts and Estates (2017)

*This award is conferred by Best Lawyers. A description of the selection methodology can be found at: https://www.bestlawfirms.com/methodology. No aspect of this advertisement has been approved by the Supreme Court of New Jersey.

Recognized in The Best Lawyers in America® for Commercial Litigation (2010-2027), Litigation – Labor and Employment (2011-2027), Litigation – Trusts and Estates (2011-2027), Litigation – Intellectual Property (2013-2027)

*This award is conferred by Best Lawyers. A description of the selection methodology can be found at: https://www.bestlawfirms.com/methodology. No aspect of this advertisement has been approved by the Supreme Court of New Jersey.

AV® Preeminent™ Peer Review Rated by Martindale-Hubbell

*This award is conferred by Martindale-Hubbell. A description of the selection methodology can be found at www.martindale.com/ratings-and-reviews. No aspect of this advertisement has been approved by the Supreme Court of New Jersey.

Pennsylvania Super Lawyer, Super Lawyers by Thomson Reuters  (2005–2025)

*Super Lawyers, part of Thomson Reuters, is a rating service of outstanding lawyers from more than 70 practice areas who have attained a high degree of peer recognition and professional achievement. The annual selections are made using a patented multiphase process that includes a statewide survey of lawyers, an independent research evaluation of candidates and peer reviews by practice area. The result is a credible, comprehensive, and diverse listing of exceptional attorneys. Selection methodology can be found at Selection process – Super Lawyers.  No aspect of this advertisement has been approved by the Supreme Court of New Jersey.

Memberships

American Bar Association

Montgomery County Bar Association

Philadelphia Bar Association

Fellow, American College of Trial Lawyers

 

State Bar Licenses

Pennsylvania, New Jersey

Court Admissions

U.S. District Ct., E.D. of Pennsylvania
U.S. District Ct., M.D. of Pennsylvania
U.S. District Ct., W.D. of Pennsylvania
U.S. District Ct., District of New Jersey
U.S. Court of Appeals, 3rd Circuit
U.S. Court of Appeals, Federal Circuit

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