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Kasowitz Benson Torres LLP

Work +1 212 506 1700
Fax +1 212 506 1800

Mark P. Ressler

Work (212) 506-1752
Kasowitz Benson Torres LLP

Work Department



Antitrust Litigation; Banking and Capital Markets Litigation; Commercial Litigation; Complex Financial Products Litigation; Intellectual Property Litigation; Investigations and White Collar Defense; Plaintiffs' Litigation; Real Estate and Hotel Litigation; Securities Litigation; Software Litigation


Mark P. Ressler is a nationally recognized litigator and former federal prosecutor whose practice spans a wide range of high-stakes commercial disputes and cutting-edge technology matters. His successful representation of corporations, financial firms, government entities and individuals has earned him recognition in Chambers USA, The Best Lawyers in America, Benchmark Litigation, Super Lawyers and other publications. He is also an accomplished criminal defense lawyer who has represented clients in virtually every type of white collar investigation.

In the technology sector, Mark has established the country’s leading practice devoted to representing companies and government entities facing the business disruption and financial losses caused by failed software implementations involving Enterprise Resource Planning (“ERP”) business software. He has become the counsel of choice for companies, states and municipalities seeking to obtain recovery from consulting firms and software providers in connection with mission-critical software projects plagued by delayed or disastrous go-lives, deficient project management, missing functionality, defective interfaces and other problems.

Companies have turned to Mark to serve as national counsel when faced with lawsuits in multiple jurisdictions across the country. He has been tapped as replacement counsel, in the middle of discovery or on the eve of trial, to turn around troubled litigations. He has also handled prominent litigations in the art and publishing worlds.

Mark was an Assistant U.S. Attorney in the Eastern District of New York, where his notable prosecutions included corruption charges against an SEC attorney, insider trading charges against a celebrity CEO, securities fraud charges against an investment banker Fortune magazine dubbed the "Hannibal Lecter of Wall Street" and racketeering trials against some of New York's most feared drug and murder-for-hire gangs. Mark was twice awarded the Justice Department's Director's Award for Superior Performance, and was chosen as the Federal Law Enforcement Foundation's "Prosecutor of the Year."

Mark has served on the Judiciary Committee of the New York Bar Association, where he assisted in evaluating all federal and state judges and prospective judges in New York. He has also been consulted by and quoted in the New York Times, the Wall Street Journal, Business Week, Fortune and other publications concerning criminal law, trial strategy and other legal matters.


New York; U.S. District Court, Eastern District of New York; U.S. District Court, Southern District of New York; U.S. Court of Appeals, Second Circuit


New York University School of Law (J.D., 1987); University of Stockholm (Graduate Diploma, International Legal Studies, Fulbright Scholar, 1988); Brown University (B.A., magna cum laude)

United States: Dispute resolution

General commercial disputes

Within: General commercial disputes

Kasowitz Benson Torres LLP 'is able to staff cases with top-tier specialists in various disciplines'; the firm maintains a focus on high-stakes litigation, covering everything from breach of contract to defamation to trade secrets disputes. It is particularly strong in the financial services, private equity and real estate sectors, though its clients operate in myriad industries beyond these. In the Eastern District of California, 'gifted strategist' Mark Ressler represented Copart as plaintiff in litigation arising out of a botched software project; after a four-week jury trial, the client was awarded $20m in damages for negligence. Tad O’Connor has 'a strong strategic overview of his cases' and 'very significant trial experience, including in the UK and continental Europe'. In a cross-border case, he worked alongside UK counsel to successfully defend private equity firm TPG at the London High Court in a long-running dispute relating to a previous investment in a Greek company. San Francisco-based Jason Takenouchi is highly recommended. Other key figures in the team include Marc Kasowitz, Michael Bowe and Christine Montenegro. Named partners are based in New York unless otherwise stated.

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