Our Locations

Constantine Cannon LLP

335 Madison Avenue, 9th Floor
New York, NY 10017
T: 212.350.2700
F: 212.350.2701

New York

New York City was our first location in 1994, and remains our largest office, representing domestic and international clients ranging from large multinational corporations, to emerging companies, industry groups, non-profits, individuals, and whistleblowers. Located by Grand Central Station, the office...
Constantine Cannon LLP

1001 Pennsylvania Ave, NW, Suite 1300N
Washington, DC 20004
T: 202.204.3500
F: 202.204.3501

Washington D.C.

Our Washington, D.C. office, located between the U.S. Capitol and the White House, serves clients nationally and internationally in a broad range of practice areas, including: Government Affairs, Intellectual Property and Technology, Antitrust Litigation and Counseling, and Whistleblower Representation.  The...
Constantine Cannon LLP

150 California Street, Suite 1600
San Francisco, CA 94111
T: 415.639.4001
F: 415.639.4002

San Francisco

Our San Francisco office opened in 2015 and offers services to a diverse range of clients, from whistleblowers, to public entities, and companies in a variety of industries. Our San Francisco attorneys practice throughout the state and nationally, working closely with...
Tower Bridge London leading specialist UK
Constantine Cannon LLP

90 Bartholomew Close London EC1A 7BN
T: +44 (0)20 3959 0700
F: +44 (0)20 3668 5601


At Constantine Cannon LLP in London, you will find three leading international practices: Antitrust Law & Competition Counseling Art and Cultural Property Law Group Whistleblower Representation Constantine Cannon LLP in London is a specialist legal practice. We are affiliated with...