Sullivan
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Sullivan litigators bring decades of first chair trial experience to a wide arrange of disputes involving clients’ activities throughout the world. 

We regularly defend and prosecute claims on behalf of our clients on an ever-expanding range of issues, including disputes arising under the U.S. securities laws, domestic and cross-border commercial contract disputes, intra-corporate disputes, cross-border trade and commodity issues, insurance coverage disputes, and employment matters. Our cases have been venued in courts throughout the United States and England. We also regularly appear before international arbitration tribunals seated in New York, London, and elsewhere, administered by an equally wide array of organizations including the ICC, LCIA, and ICDR. 

Beyond traditional courtroom work, our litigators excel at assisting out clients in avoiding litigation. We regularly counsel clients on risk avoidance and mitigation, both during contract formation and the early stages of a dispute, all designed to protect our clients’ interests in an efficient and cost effect manner.

Representative Client Work

  • Successfully obtained a unanimous defense jury verdict for Sogeti (a Capgemini subsidiary) in a jury trial in Tampa, Florida, where plaintiff, a former employee, asserted race discrimination and retaliation claims seeking seven figures in damages
  • Argued in the Supreme Court of the United States as lead counsel to plaintiffs seeking restitution of the Guelph Treasure, sold under duress by Jewish art dealers in 1935 to the Prussian government. F.R.G. v. Philipp, 141 S. Ct. 703 (2021). The case concerns the first case in which a U.S. court has found jurisdiction over a German state museum for claims to allegedly Nazi-looted art, Philipp v. F.R.G., 894 F.3d 406 (D.C. Cir. 2018)
  • Obtained a judgment of more than $40 million for a European bank against a Middle Eastern bank for the failure to reimburse on a so-called synthetic letter of credit. The defendant attempted to avoid reimbursement claiming it was not subject to jurisdiction and was defrauded in connection with the underlying transaction
  • Represented independent trustees and mutual funds in various disputes with their advisors and/or third-party service providers. These matters are generally highly confidential, complex disputes requiring detailed factual analyses and involving arcane issues arising under the Investment Company Act of 1940
  • Represented banks and financial institutions in domestic and international litigation and arbitration involving trade credit insurance disputes
  • Representing companies in toxic tort and environmental exposure cases, including the determination and allocation of liabilities and actions against other potential responsible parties and their insurance providers
  • Following trial, successfully negotiated resolution of a complicated dispute over a 62-year ground lease involving approximately four acres in the Kendall Square area of Cambridge, Massachusetts
  • Represented a national insurance and financial securities company in numerous litigations, workouts and negotiated resolutions of securities, fiduciary and other claims arising out of three mezzanine investment funds
  • Represented a foreign manufacturer of optical fiber in a successful multimillion-dollar breach-of-contract claim against a domestic customer
  • Defended a unit of a major international accounting firm in lawsuits arising from the collapse of a software company
  • Represented both purchasers and sellers of companies and assets in post-closing disputes including alleged breach of representations and warranties, balance sheet adjustments, valuation controversies and indemnification rights
Viewpoints
All Viewpoints
California Jury Stamps Its Approval on SEC’s Novel Shadow Trading Theory
Showcasing its shadow trading theory in a case of first impression, the U.S. Securities and Exchange Commission (SEC) secured a favorable verdict in a closely watched case. After hearing testimony over eight days of trial, a federal jury in California needed only two hours of deliberations to find a former executive liable for using material non-public information concerning his company to trade in the stock of another “similarly situated company,” the novel definition of shadow trading. Under a civil misappropriation theory of insider trading, the jury found by a preponderance of the evidence that Matthew Panuwat used inside information about the potential purchase of his company, Medivation, Inc., to trade in the stock of Incyte Corporation, another pharmaceutical maker of cancer treatments. The SEC’s evidence included that Panuwat bought call options seven minutes after the Medivation CEO sent him an email detailing that Pfizer Inc., a top contender to acquire Medivation, was close to signing a deal. According to the SEC, Panuwat used that inside information to purchase call options in Incyte and, therefore, violated well-known insider trading laws. At this point, the first-of-its-kind verdict portends that the SEC will steadfastly continue to pursue shadow trading cases.     Whether shadow trading cases are here to stay is another question altogether, however, as Panuwat will likely appeal. Also, given that the SEC’s burden of proof was by a preponderance of the evidence, not a higher burden as with clear and convincing evidence or beyond a reasonable doubt, it is noteworthy that the U.S. Department of Justice sat this one out. The absence of a parallel criminal investigation of Panuwat’s trading by the DOJ suggested a wait and see approach so it could observe the SEC’s case and outcome. Post verdict, the DOJ may now be less willing to remain idle in cases involving shadow trading. All companies, public and private alike, are on notice and would be well-served to supplement their insider trading policies to include cautionary guidelines and procedures on shadow trading.   
A Better Way To Consider Collateral Consequences of Conviction
Christopher Shields co-authored the article, "A Better Way To Consider Collateral Consequences of Conviction," published by the New York Law Journal. The article discusses how it's time for federal courts to more consistently appraise more realistically all consequences that a criminal conviction has on a defendant.
Sullivan Advises BAFT and ITFA on Updated CRR Legal Opinions for the 2008 English Law Master Participation Agreement (MPA)
(London and New York) – Sullivan has advised BAFT (the Bankers Association for Finance & Trade) and ITFA (the International Trade and Forfaiting Association) on the publication of the two Capital Requirements Regulation (CRR) legal opinions covering the 2008 English law Master Participation Agreement (MPA). The newly released opinions comprise the EU CRR opinion on English law MPA 2008 and the UK CRR opinion on English law MPA 2008. They are intended for institutions that continue to use the 2008 version of the MPA, having executed it prior to the introduction of the later versions. The publication of these two legal opinions completes the suite of updated CRR legal opinions that Sullivan has prepared for BAFT and ITFA, following the release of the updated opinions covering the other English law MPAs, New York law MPAs and the Surety MPAs earlier this year, which can be read in full, here. Importantly, these opinions note that eligibility for credit risk mitigation (CRM) may only apply if the Participant shares in the fraud risk in the optional wording of Clause 11. As the 2008 English law MPA has long since been superseded, ITFA has announced that these are the final legal opinions that will be issued in respect of that document, reflecting both the age of the underlying template and the increasing difficulty of providing a clean opinion where one of the optional wordings is adopted. Geoffrey Wynne, head of Sullivan’s Trade & Export Finance Group, commented: “We are pleased to have continued our long-standing work with BAFT and ITFA advising on these CRR legal opinions for the 2008 English law MPA. Their publication completes the current suite of opinions available to members and provides support for institutions that continue to use the earlier version of the agreement. It is hoped that institutions will pay heed to reservations and react accordingly.” The Sullivan team advising BAFT and ITFA includes partners Geoffrey Wynne and Marian Boyle in London and partner Natalie Lederman in New York. About Sullivan Sullivan & Worcester (Sullivan) is a global law firm with lawyers in Boston, London, New York, Tel Aviv and Washington, D.C. Sullivan’s clients, including Fortune 500 companies, leading financial services firms and asset managers, boards of directors and emerging businesses, rely on Sullivan’s ability to navigate complex legal and operational landscapes and its commitment to best in class client service. For further information, please visit the firm’s website and LinkedIn.
Sullivan & Worcester Achieves National and Regional Rankings in 2026 Best Law Firms® Listings
Boston, MA – Sullivan & Worcester is pleased to announce that the firm has been recognized in the 2026 Best Law Firms® rankings. Twelve practice areas achieved national rankings and 19 practice areas were recognized regionally. Best Law Firms 2026 recognizes only the top 3.8 percent of law firms nationwide. Independently produced by Best Lawyers, the 2026 rankings were compiled from more than 110,000 client references, surveys of 70,000 peer lawyers and nearly 1,000 firm leadership interviews. Sullivan achieved the following rankings in 2026: National Tier 1 Commercial Litigation Corporate Law Environmental Law Mutual Funds Law Trusts and Estates National Tier 2 Bankruptcy and Creditor Debtor Rights / Insolvency and Reorganization Law Litigation and Controversy - Tax Mergers and Acquisitions Law Real Estate Law Securities Regulation Tax Law National Tier 3 Litigation – Bankruptcy Metropolitan Tier 1 Boston Bankruptcy and Creditor Debtor Rights / Insolvency and Reorganization Law Commercial Litigation Corporate Governance Law Corporate Law Employee Benefits (ERISA) Law Environmental Law Litigation - Bankruptcy Litigation and Controversy - Tax Mergers and Acquisitions Law Real Estate Law Tax Law Trusts and Estates New York City Corporate Law Trusts and Estates Washington, D.C. Mutual Funds Law Securities Regulation Metropolitan Tier 2 Boston Corporate Compliance Law Patent Law New York City Mutual Funds Law Washington, D.C. Corporate Law Metropolitan Tier 3 Boston Land Use and Zoning Law Nonprofit / Charities Law Washington, D.C. Private Funds / Hedge Funds Law About Sullivan Sullivan & Worcester (Sullivan) is a global, mid-sized law firm with lawyers in Boston, London, New York, Tel Aviv and Washington, D.C. Sullivan’s clients, including Fortune 500 companies, leading financial services firms and asset managers, boards of directors, real estate companies and emerging businesses, rely on Sullivan’s ability to navigate complex legal and operational landscapes, the impeccable judgment of its lawyers and its commitment to best‑in‑class client service.