Since the explosion of M&A transactions in the late 1970s, Sullivan & Cromwell has represented clients in every type of litigation arising out of such transactions in federal and state courts all over the country, including frequently in the Delaware Chancery and Supreme state court, the most influential courts on corporate governance matters in the United States.
The Firm has handled hostile takeover litigation and shareholder class and derivative actions in every conceivable takeover-related setting, including actions related to disclosure, defensive-measure and going-private transactions.
S&C has also defended special committees and handled regulatory matters relating to M&A transactions involving antitrust, insider trading, and disclosure issues.
From advice on deal structure to victory at trial, the Firm's formidable litigation experience in M&A transactions provides essential support to its M&A clients.


Some of S&C’s recent experience with M&A litigation includes representations of:
  • 1st Century Bancshares, Inc. and former board members in obtaining the dismissal–upheld on appeal, ultimately to the California Supreme Court–of a putative class action stemming from 1st Century’s acquisition by Midland Financial Co., the holding company of MidFirst Bank—one of the nation’s largest privately-held banks. This was the first ruling validating a Delaware forum selection bylaw under California state law. 
  • AMC Networks Inc. and the board of RLJ Entertainment, Inc. (RLJE) in obtaining a  dismissal of a stockholder derivative action challenging AMC’s $59 million acquisition of RLJE, which was completed in October 2018. 
  • Amgen in litigation relating to numerous acquisitions, including its recent acquisitions of Onyx Pharmaceuticals and Micromet. In the Micromet litigation, S&C defeated plaintiffs’ motion for a preliminary injunction, which was decided by the Delaware Chancery Court shortly before the transaction was scheduled to close. 
  • AT&T in an appeal of a settlement in a shareholder class action stemming from AT&T’s acquisition of Leap Wireless International, Inc., as well as in appraisal proceedings brought in connection with AT&T’s acquisitions of DirecTV and Time Warner.
  • Columbia Pipeline Group and its board in shareholder class action litigations in Delaware Chancery Court and in Texas federal court challenging the $13 billion acquisition of Columbia Pipeline by TransCanada, which closed in July 2016. The Delaware Chancery Court dismissed the action in March 2017. The deal closed on July 1, 2016. 
  • Cytec Industries and its board in shareholder class action litigations in Delaware federal court and in New Jersey Chancery Court challenging the $5.5 billion acquisition of Cytec Industries by Solvay, which was completed in December 2015. After defendants moved to dismiss the New Jersey action, plaintiffs voluntarily dismissed that action. S&C then successfully defeated a request to expedite the Delaware litigation, and that litigation was dismissed voluntarily in February 2016. 
  • DS Smith, in litigation in the Southern District of New York relating to the acquisition of DS Smith’s packaging business by Liqui-Box, an entity controlled by Olympus Partners. DS Smith claims that Olympus has breached its obligations relating to antitrust approval under the terms of the parties’ stock purchase agreement, while Olympus makes contrary claims. 
  • Enbridge Inc., its directors, and subsidiary Enbridge Pipelines (Alberta Clipper) L.L.C. as lead counsel in a class action litigation and derivative suit arising from Enbridge Energy Partners, L.P.’s purchase of a 66.67% interest in the American segment of the Alberta Clipper pipeline from its general partner in 2015, which included a ruling from the Delaware Supreme Court fundamentally changing the law on the application of the “entire fairness” doctrine. S&C also represented Enbridge in shareholder litigation arising from its $43 billion acquisition of Spectra Energy Corp. in 2016. 
  • First Horizon National Corporation in defending against a class action and a separate appraisal proceeding in Delaware Chancery Court related to first Horizon’s $2.13 billion acquisition of Capital Bank Financial Corp., which closed in November 2017. 
  • Goldman Sachs in obtaining dismissal of all claims in a class action in Delaware concerning the acquisition of Blount by a private equity consortium. 
  • Hudson City Bancorp, Inc. (HCB) and its former directors in obtaining the dismissal of a putative class action shareholder suit stemming from the $3.7 billion merger between HCB and M&T Bank, which was approved by shareholders in April 2013 but not completed until November 2015. The merger was subject to increased regulatory scrutiny because it made M&T one of the nation’s 25 largest banks. 
  • Illinois Tool Works (ITW) in successfully resolving litigation relating to ITW’s purchase in 2012 of Brooks Instrument, LLC from the defendant private equity firm. The case was resolved on the eve of trial following the court’s denial of the defendant’s motion for summary judgment and the defendant’s Daubert motion with respect to ITW’s damages expert. 
  • IntercontinentalExchange in class actions in Delaware and New York brought by NYSE stockholders arising out of the NYSE’s acquisition by ICE for a total of approximately $8.2 billion. S&C successfully obtained a stay of the New York litigation in favor of the Delaware action, and shortly thereafter the Delaware court denied a preliminary injunction motion. The plaintiffs thereafter voluntarily dismissed the cases. 
  • JPMorgan Securities in litigation in Delaware Chancery Court relating to the sale of The Fresh Market to an affiliate of Apollo Capital Management LLC. JPMorgan served as financial advisor to The Fresh Market. 
  • Lion Tree Holdings in litigation in Delaware Chancery Court alleging that Lion Tree aided and abetted alleged breaches of fiduciary duty by its client the Presidio board of directors, and Presidio’s controlling shareholder in connection with Presidio’s acquisition by BCP Ventures.
  • Ruckus Wireless Inc. and its directors in connection with litigation relating to the proposed acquisition of Ruckus by Brocade Communications Systems Inc. Prior to closing, litigation challenging the merger was filed in California Superior Court and in the United States District Court for the District of Delaware. The District of Delaware plaintiffs filed a motion for a preliminary injunction seeking to enjoin the closing of the tender offer, but withdrew their motion after S&C filed an opposition on behalf of Ruckus and its directors rather than file a reply brief. The District of Delaware litigation was later voluntarily dismissed. Following the closing of the tender offer, a separate action was filed in the United States District Court for the Northern District of California. S&C represented the individual defendants in that litigation, which was dismissed with prejudice in June 2017. 
  • Solera Holdings, Inc. in obtaining the dismissal with prejudice of a complaint filed by a putative class of former Solera shareholders, which alleged the defendants breached their fiduciary duties in connection with the approval of Vista Equity Partners’s $6.5 billion acquisition of Solera. 
  • Syntel and its former directors in a putative class action in state court in Michigan seeking damages in connection with the acquisition of Syntel by Atos. S&C successfully obtained dismissal of the complaint on the ground that under Michigan law the claims being asserted were derivative, not direct. After filing a notice of appeal, plaintiffs elected to drop it. 

  • Tiffany & Co. as plaintiff in litigation against LVMH Moet Hennessy Louis Vuitton stemming from LVMH’s acquisition of Tiffany for approximately $16 billion, which was completed in January 2021.
  • Volcano Corporation in obtaining the dismissal of the Verified Consolidated Amended Class Action Complaint filed by Philips Holding USA Inc. former shareholders. The Delaware Court of Chancery held that a solid tender-off ratification was protected under the business judgment rule. S&C originally represented Philips, as the acquirer, as part of the same briefing. After the transaction closed, and with Philips’ acquisition of Volcano, S&C became counsel to Volcano, working with all of the other defendants (as indemnified parties) to focus the briefing.