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

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

Latest News, Publications & Speeches

Dec82021
Former Regional Director of the SEC’s Chicago Office Joins Constantine Cannon’s Whistleblower Practice

Joel R. Levin brings deep experience to the largest and most successful international whistleblower practice in the world NEW YORK, NY (12/3/2021)—Constantine Cannon LLP is...

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Dec82021
Constantine Cannon LLP Announces Three Partnership Promotions

Hamsa Mahendranathan, Sarah “Poppy” Alexander, and Ari Yampolsky join the partnership ranks of the largest and most successful international whistleblower practice in the world NEW...

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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

Nov212021
On the anniversary of the Gettysburg Address, we should follow Lincoln’s lead
Edward Baker

Whistleblower attorney Edward Baker was published in The Patriot News, On the anniversary of the Gettysburg Address, we should follow Lincoln’s lead (November 21, 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

November 15, 2021

The whistleblower award to Constantine Cannon client Gwang Ho Kim received extensive press coverage, including: NHTSA issues first-ever whistleblower award of $24M to Hyundai insider, Compliance Week. U.S. Auto-Safety Regulator...

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