Gregg is the global co-head of the firm's litigation and enforcement practice group, based in Ropes & Gray’s New York office. Gregg has a long track record of delivering successful results to financial institutions, Fortune 500 companies, professional services organizations, private equity, and other sophisticated clients in a wide range of complex commercial disputes. His practice principally involves matters concerning the federal securities laws, commercial contracts, bankruptcy-related proceedings, financial transactions/instruments, corporate governance, breach of fiduciary duty claims and mergers and acquisitions. Gregg also frequently represents real estate developers, investors and owners in high-profile litigation matters.

A frequent speaker and author on commercial law topics, Gregg’s work has been published in New York Law Journal, Bank Director and Business Law Today, in addition to numerous PLI and Bar Association publications.

Gregg has been recognized by Chambers USA: America’s Leading Lawyers for Business as a leading individual in General Commercial Litigation, by Benchmark Litigation as a Litigation Star for General Commercial and Securities work, and by Legal 500 in the following litigation categories: Securities: Shareholder Litigation; and Commercial Litigation. As reported by Chambers, clients have described Gregg’s work as “exceptional” and “first class,” while commending him for being “incredibly bright, very thoughtful and focused” and “a brilliant tactician.”


  • Won dismissal of a putative class action lawsuit brought in the Southern District of New York against TG Therapeutics, Inc. and three of its officers, which alleged securities fraud in connection with public disclosures about certain drugs developed by the company. Following oral argument, the Court granted our motion to dismiss with prejudice.
  • Representing a leading global private equity firm and related entities and individuals in a number of lawsuits related to a former portfolio company’s default on high-yield debt. The plaintiffs, which include liquidators, an indenture trustee and bondholders, asserted claims in excess of $2 billion in multiple actions brought in state and federal courts. We obtained numerous dismissal orders for our clients at both the motion to dismiss phase and on summary judgment. In March 2024, obtained a significant decision from the Appellate Division of the New York Supreme Court, effectively ending more than 12 years of state and federal court litigation and dismissing the remaining claims brought against our client.
  • Counsel to financial institution in international arbitration concerning dispute with majority owner of Latin American telecommunications company. The tribunal issued a unanimous ruling granting our client’s request for specific performance requiring a sale of the company to a third party. The decision was recently confirmed by the Second Circuit.
  • Won dismissal with prejudice of a securities class action brought against a syndicate of underwriters in the Eastern District of New York challenging statements made by Playtika Holding Corp., a technology company that develops free-to-play mobile games, in connection with its January 2021 IPO. The complaint asserted claims under Section 11 of the Securities Act against the underwriters, Playtika, and certain Playtika directors on behalf of a purported class of Playtika shareholders.
  • Obtained dismissal of $1 billion in fraudulent conveyance claims in the Southern District of New York as lead defense counsel for funds, including Vanguard, Blackrock and Fidelity that invested in Jones Group Inc. (later known as Nine West) prior to its leveraged buyout and subsequent bankruptcy recently confirmed by the Second Circuit.
  • Won dismissal of a consolidated putative securities fraud class action lawsuit against a syndicate of underwriters led by Deutsche Bank Securities Inc. in U.S. District Court for the District of Nevada. Plaintiffs alleged that underwriters were liable under Sections 11 and 12(a)(2) of the Securities Act for allegedly false and misleading statements in the Shelf Registration Statement and Prospectus Supplements issued in connection with two public offerings of Play AGS, Inc., a developer, manufacturer and operator of casino games, systems and technology.
  • Representing a portfolio company of a large infrastructure fund in class action in the US Virgin Islands arising from alleged public nuisance.
  • Representing the plaintiff homeowners in the New York federal class action Dorce v. City of New York challenging the constitutionality of New York City’s property seizures under its Third Party Transfer program. The Ropes & Gray team successfully obtained a reversal on appeal at the Second Circuit rejecting the City’s jurisdictional challenges.  
  • Representing Fortress Biotech, Inc. and its officers in a putative federal class action in the Eastern District of New York, in which plaintiffs allege Fortress failed to disclose various facts and circumstances with respect to a New Drug Application filed by its affiliate regarding that company’s lead product candidate. 
  • Representing a large asset manager in defense of a claim arising out of the purchase of $150 million of claims in the Lehman bankruptcy. The seller claimed our client breached the agreement and the duty of good faith in blocking a condition triggering an additional $20 million payment for the purchased bankruptcy claims. Judge Schecter of the NY Commercial Division recently granted our motion to dismiss the complaint.
  • Represented Stemline Pharmaceuticals and its officers and directors in a putative class-action securities fraud litigation arising from Stemline’s alleged failure to disclose adverse events in a clinical drug trial that occurred just prior to a $50 million public offering of securities. The Court granted our motion to dismiss. 
  • Representing a group of underwriter defendants in class action securities litigation related to alleged misstatements made by AmTrust Financial Services. Our clients underwrote two offerings of AmTrust stock which plaintiffs allege give rise to claims under Sections 11 and 12(a)(2) of the Securities Act.
  • Represented the Official Committee of Unsecured Creditors of oil producer Sabine Oil & Gas Corporation in Chapter 11 proceedings in the SDNY. The case is among the largest in the wave of bankruptcy cases affecting the oil and gas industry.
  • Represented RFR Realty in an action by lender to enforce US $140 million personal guaranty on defaulted mortgage involving 610 Lexington Avenue in New York City. The Court dismissed lender’s claim.*
  • Represented Centerbridge Partners, L.P. in connection with tort claims brought by mezzanine debt holders arising out of the bankruptcy of Extended Stay Hotels (ESH), the largest hotel chain to file for chapter 11. The Court dismissed all of the claims against Centerbridge.*
  • Represented LNR Partners, as the servicer of a US $133m loan in a foreclosure action and related motion for the appointment of a receiver based on the misconduct of the property manager.*
  • Represented founder and CEO of specialty lending business in arbitration against Emigrant Bank involving a dispute over a call option to buy out founder’s shares at a fixed price and founder’s right to trigger a sale of the business to a third party. The arbitration panel found that Emigrant had waived its Call option, ordered the third party sale process to proceed, and awarded our client all of its attorneys’ fees and other arbitration expenses as the prevailing party. The Award was confirmed by Judge Carter (SDNY). We then prevailed in a lengthy follow-on arbitration relating to the sale of the business, including a further award of over $2 million in attorneys’ fees. The award was recently confirmed by Judge Nathan (SDNY).
  • Representing Costco in an action filed in the SDNY arising out of the multi-billion dollar Ponzi scheme perpetrated by Tom Petters. The plaintiff, Ritchie Capital, alleged that Costco conspired with Petters and aided and abetted the Ponzi scheme, which involved fabricated purchase orders pursuant to which Costco allegedly had agreed to buy millions of dollars of name brand electronics from Petters. The plaintiffs were seeking in excess of $30 million in damages. The Court granted Costco’s motion to dismiss, and the decision was affirmed by the Second Circuit.
  • Representing a subsidiary of Deutsche Bank, German American Capital Corporation (GACC), in litigation filed in New York Supreme Court arising out of the borrower’s default on the mortgage and mezzanine loans related to a luxury condominium project in Tribeca in Manhattan. The Court granted GACC’s motion to dismiss. The matter was then affirmed on appeal to the First Department.
  • Represented Genstar Capital in action alleging tortious interference and violation of the Connecticut Unfair Trade Practices Act by the seller of a business purchased by Genstar. After the completion of discovery, the Court granted Genstar’s motion for summary judgment.
  • Representing Barthelemy Holdings, LLC and related entities (“Barthelemy”), as well as Colony Capital, LLC and related entities (“Colony”), in a lawsuit filed in Delaware Chancery Court in connection with a luxury hotel and villa development project on the French island of Saint Barthelemy. Following oral argument in connection with expedited proceedings, the Court denied plaintiff’s motion for a preliminary injunction seeking to halt a transaction in connection with the foreclosure proceedings. Subsequently, the Court granted a motion to stay the proceeding.
  • Trial counsel to class of taxicab drivers on claims for breach of due process in connection with suspension of their licenses. See Nnebe v. Daus (2nd Cir. 2019).
  • Represented a medical device maker in an arbitration in which a major supplier sought to terminate the parties’ distribution agreement. The arbitrator issued a preliminary injunction enjoining termination of the agreement and the matter settled favorably after a week in hearing.
  • Represented Brookfield Office Properties in two securities class actions, a common stock action in California and a preferred stock action in Maryland, arising out of Brookfield’s acquisition of MPG, a publicly traded REIT. In the Maryland action, after oral argument, the Court denied plaintiffs’ motion for a preliminary injunction.
  • Represented a group of bank defendants, including Barclays, Wells Fargo and Deutsche Bank, among others in a putative, US $5 billion class action brought on behalf of minority owners of oil and gas leases with Chesapeake Energy Corp. Defendants’ motion to dismiss was granted and the decision was affirmed on appeal by the Second Circuit.*
  • Represented MRC Global in an action brought in the Delaware Court of Chancery by a former shareholder claiming that MRC Global failed to comply with the provisions of a merger agreement requiring it to promptly use commercially reasonable efforts to sell certain assets for the benefit of the former shareholders. Plaintiff dropped its claims after oral argument on summary judgment before Chancellor Strine.*
  • Lead trial counsel in an arbitration arising out of a dispute between the owner of a hotel chain and its joint venture partner, a well-known Manhattan developer. After a week-long arbitration, the arbitrator ruled that the developer would have to pay virtually all of the costs at issue, and awarded our client its attorney’s fees, expert fees and arbitration expenses of $1.23 million. The award was recently confirmed by Justice Scarpulla of the NY Commercial Division. 
  • Representing a lender in successful defense of litigation brought in Delaware Chancery Court by borrower alleging lender misconduct arising out of a foreclosure on a luxury resort development project. After expedited briefing and an oral argument, the Chancery Court denied borrower’s motion for a temporary restraining order seeking to halt a transaction in connection with the foreclosure proceedings.
  • Counsel to Olshan Properties in a dispute with The Limited concerning the right of first offer for a hotel project that would compete with a hotel jointly owned and developed by Olshan/The Limited.
  • Represented Maestro West Chelsea SPE LLC in an action to enforce its contractual right to buy air rights next to the Highline Park in Manhattan. Also successfully defended client against US $75 million in counterclaims. The Court granted Maestro’s motion for a preliminary mandatory injunction.*

Representations denoted with an asterisk were completed prior to joining Ropes & Gray.

Areas of Practice