Mark A. Grannis



Mark Grannis helps find creative solutions to a wide variety of legal problems for his clients. His caseload typically includes litigation matters (both trial and appellate) as well as regulatory advocacy. He also mediates disputes for other litigants, and serves as a court-appointed mediator in the D.C. Superior Court, the U.S. District Court for the District of Columbia, and the U.S. Court of Appeals for the D.C. Circuit. He is comfortable standing up to bullies, and equally comfortable negotiating amicable resolutions among formerly bitter adversaries.

Trial Litigation. Mr. Grannis has litigated civil cases including commercial and financial disputes, constitutional rights, election contests, product liability claims, antitrust issues, and probate matters. He is admitted to practice in D.C., Maryland, New York, and California, and has appeared in a large number of federal, state, and territorial courts. Some of Mr. Grannis’s notable trial litigation matters include:

  • Obtaining compensation for a journalist whose notes were seized in violation of the Privacy Protection Act;
  • Successfully defending a foreign exchange broker against a customer’s attempt to shift losses in the foreign exchange markets;
  • Cornering the Department of Justice into one of the largest Privacy Act settlements in history—and complete exoneration—for a client whom federal officials had publicly smeared in the government’s investigation of the anthrax attacks;
  • Stopping the Department of Labor from interfering with attorney-client relationships; and
  • Vindicating the reputations of victims of libel and slander.

Appellate Litigation. Mr. Grannis’s appellate experience includes cases in the United States Supreme Court, several U.S. Courts of Appeals, and appellate courts in California, New York, and Maryland. These cases have raised issues as common as the review of administrative agency decisions and as esoteric as the proper interpretation of the Bill of Attainder Clause. Most recently, Mr. Grannis has:

  • Revived a commercial real estate developer’s meritorious claims of government corruption and bad faith in contracting;
  • Fought for ballot access and other benefits for political parties unfairly excluded by state election procedures;
  • Blocked state regulatory action against companies subject to exclusively federal regulatory jurisdiction; and
  • Obtained reversal of a summary judgment erroneously entered against a privately owned nursing home that subsequently won over $20 million at trial.

Regulatory Advocacy. Mr. Grannis also has extensive experience solving regulatory problems, primarily concerning telecommunications. He has represented equipment manufacturers and service providers in matters before the Federal Communications Commission, primarily in the area of radio frequency spectrum management. These representations have frequently required complementary efforts at the International Telecommunication Union, the U.S. Departments of State and Commerce, and with foreign regulatory authorities. In the field of telecommunications regulation, Mr. Grannis has:

  • Negotiated a successful resolution of several interrelated disputes between the U.S. Department of Energy and a major appliance maker;
  • Pioneered development of new licensing and regulatory strategies for non-geostationary communications satellites;
  • Represented service providers and equipment manufacturers in administrative rulemakings on use of the radio frequency spectrum;
  • Advised companies and non-profit organizations on compliance with the federal “Do Not Call” rules and other telemarketing regulations administered by the FCC and the Federal Trade Commission; and
  • Represented terrestrial wireless infrastructure provider at international conferences addressing world-wide frequency allocations.

Before founding Harris, Wiltshire & Grannis, Mr. Grannis worked at well-respected firms in Los Angeles and Washington. He also spent two years working at the FCC, where he helped to create the FCC International Bureau and to consolidate all the regulations governing international and satellite communications.

Mr. Grannis has earned an AV rating from Martindale-Hubbell, and has been recognized for excellence by Best LawyersSuper Lawyers, and other publications. He is a member of the Association for Conflict Resolution, the Maryland Council for Dispute Resolution, the ADR Section of the Maryland State Bar Association, and the Maryland Program for Mediator Excellence.


University of Michigan Law School, J.D., cum laude

Georgetown University, B.A., cum laude


Hon. Stephen Reinhardt, U.S. Court of Appeals for the Ninth Circuit



At HWG, we’re always looking for smart, talented people to add to our team.


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