Experienced Trial, Antitrust, and Whistleblower Lawyers

WHAT WE DO

WORKING WITH YOU & FOR YOU

We’re a different kind of law firm. At Constantine Cannon, we listen. We apply our extensive legal knowledge and decades of experience. We work tirelessly for you from beginning to end. And together, we get results.

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Practice Groups

Antitrust Litigation & Counseling

Our attorneys are both experts in antitrust law and seasoned litigators. Our approach to every case, whether on the plaintiff’s side or the defense, is to be prepared to take the case to trial.

Whistleblower Representation

The Constantine Cannon Whistleblower Lawyer Team has extensive experience representing whistleblowers under the qui tam provisions of the False Claims Act, the Dodd-Frank Act, the IRS Whistleblower Law, and the wide array of other federal and state whistleblower reward laws.

Commercial Litigation

Constantine Cannon has broad experience representing plaintiffs and defendants in complex commercial litigations and arbitrations. Our reputation is built upon our central philosophy of aggressively and sensibly representing clients in all areas of commercial dispute.

Art & Cultural Property

We formed the Art and Cultural Property Law Group to make a total commitment to the art world. We pride ourselves in our knowledge of the art market, our legal expertise, our effectiveness, and our entrepreneurial spirit, which we share with many of our clients.

Compliance, Monitoring & Investigations

Constantine Cannon conducts efficient and effective internal reviews and investigations for its clients. We provide critical value by establishing the independence of investigations, a key issue both in seeking reduced penalties in criminal actions and in minimizing civil litigation exposure.

E-Discovery Counseling

Our e-discovery practice group, comprised of a dedicated team of attorneys, project managers, and legal technology specialists is at the forefront of e-discovery theory and practice. We work closely with our clients to tailor creative and flexible discovery plans that mitigate both costs and litigation risk.

Government Affairs

Constantine Cannon has extensive experience representing clients before numerous federal and state agencies, including the Department of Justice, the Federal Trade Commission, the Federal Communications Commission, the Federal Reserve Bank, and the Attorney General of every state active in antitrust enforcement.

Intellectual Property & Technology

We represent high technology companies in the consumer electronics, software, internet, webcasting, retail, and reprographics industries in a variety of matters involving copyright, trademark, trade secret, and patent law. We regularly practice before federal district courts and courts of appeals, as well as arbitrations, administrative agencies and tribunals.

Offices

NewYork
New York
Constantine Cannon

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

DC
Washington D.C.
Constantine Cannon

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

sanfrancisco
San Francisco
Constantine Cannon

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

london
London
Constantine Cannon

Regulatory Information

Privacy Policy

Diversity Statement

Complaints Policy 90 Bartholomew Close

London EC1A 7BN
T:+44 (0)20 3959 0700

Latest News, Publications & Speeches

Sep152021
U.S. Intervenes in Whistleblower Lawsuit brought by Constantine Cannon Client against Independent Health and Related Entities for Defrauding Medicare Advantage Program

Medicare Advantage Organization and its subsidiaries allegedly ignored federal guidelines for proper coding of medical conditions for Medicare Part “C” reimbursement In a rare move,...

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September 14, 2021

Whistleblower attorney Max Voldman was quoted in a Modern Healthcare article, DOJ intervenes in False Claims Act suit against Medicare Advantage insurer. (subscription required)

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Constantine Cannon “can claim to have won two of the three largest antitrust settlements in U.S. history.” – Global Competition Review, 2012

Sep92021
Seven Constantine Cannon Attorneys Recognized in Lawdragon’s “500 Leading Plaintiff Financial Lawyers in America in 2021” Edition

Constantine Cannon is pleased to announce that seven of its attorneys have been named to Lawdragon’s “500 Leading Plaintiff Financial Lawyers in America in 2021”...

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Constantine Cannon Named National Tier-1 “Best Law Firm” for Antitrust Law and Antitrust Litigation – U.S. News Best Lawyers 2020

Aug302021
Constantine Cannon Client Secures Record $90 Million False Claims Act Whistleblower Settlement with Sutter Health

Sutter Health settles closely watched whistleblower lawsuit alleging it violated the False Claims Act by submitting inaccurate and unsupported medical information on tens of thousands...

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