Delaware Litigation
Overview
Sidley’s Delaware litigation practice represents clients in their most significant and complex disputes before the Delaware courts, including the Delaware Court of Chancery, the Delaware Superior Court, the Delaware Supreme Court, and the U.S. District and Bankruptcy Courts for the District of Delaware. Drawing on our experience handling hundreds of cases across these forums, our litigation and trial teams — whose matters have established important precedents in the state — provide clients with sophisticated advocacy informed by our deep understanding of Delaware’s complex corporate, commercial, and bankruptcy laws. Additionally, our strength in Delaware matters often leads to clients retaining us for corporate law disputes in other jurisdictions that draw heavily on Delaware law.
“Sidley Austin LLP boasts a highly regarded securities litigation offering with impressive coverage of all key U.S. markets. The firm is particularly noted for its representation of issuers and their officers and directors, while also offering recognized experience of underwriter representation. It regularly handles major M&A litigation in Delaware and elsewhere, covering both breach of fiduciary duty suits and contract disputes. It has additional strength in connection with the representation of accounting firms.”
Chambers USA 2025: Nationwide - Securities: Litigation
“The firm’s expertise also extends to M&A disputes and corporate governance matters litigated in the Delaware Court of Chancery, work which also includes a considerable amount of shareholder activism matters.”
Legal 500 U.S. 2025 - Securities Litigation: Defense
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In-Depth
Committed to Excellence in Delaware Litigation
Our practice is defined by a commitment to excellent client service, strategic advocacy, and deep familiarity with the state’s courts and judges. We bring to bear the knowledge and experience that clients rely on when facing disputes involving Delaware law and in the Delaware courts. Sidley’s market-leading Enhanced Scrutiny blog, authored by thought leaders from our multidisciplinary global practice groups, provides insightful analysis on M&A and corporate governance issues from the Delaware courts and other jurisdictions to a substantial subscriber base.
Our Delaware litigation experience covers a range of legal disciplines, including:
M&A, Stockholder, and Activism Work
We draw upon the full strength of our Securities and Shareholder Litigation practice in high-stakes corporate litigation matters in the Delaware courts, including the Court of Chancery, the nation’s preeminent forum for resolving business disputes. Our lawyers are skilled in navigating the fast-paced Court of Chancery and represent boards of directors, special committees, and corporate officers in a variety of litigation matters governed by Delaware’s corporation or alternative entity law (e.g., claims for breach of fiduciary duty, M&A disputes, and books-and-records proceedings). We have extensive experience in all phases of complex M&A litigation and activism matters. Our lawyers represent clients concerning these issues, not just in Delaware, but also in courts around the country, which often look to Delaware law as persuasive guidance. We pride ourselves on collaborating with our corporate colleagues as appropriate to reach a comprehensive litigation plan that accounts for business needs and realities.
Breach of Contract and Complex Commercial Litigation
Leveraging the full strength of our Commercial Litigation and Disputes practice, we represent a range of corporate entities in breach of contract, fraud, and other complex commercial disputes, including joint venture breakups, financing disagreements, and contractual indemnification claims. Whether litigating in the Court of Chancery or the Superior Court’s Complex Commercial Litigation Division, we bring an in-depth understanding of Delaware contract law’s emphasis on freedom of contract and its sophisticated approach to interpreting commercial agreements.
IP Litigation
Our IP Litigation practice has established a strong reputation in the U.S. District Court for the District of Delaware — one of the nation’s prominent venues for intellectual property disputes. Our IP lawyers have achieved successful outcomes for clients across diverse industries, including pharmaceuticals, biotechnology, software, and telecommunications. We handle patent infringement, trade secret, copyright, trademark, and licensing disputes, drawing upon our deep bench of technically trained lawyers and our experience before both Delaware federal judges and the Federal Circuit.
Bankruptcy and Insolvency Litigation
Sidley’s Restructuring team has substantial experience representing clients at the U.S. Bankruptcy Court for the District of Delaware, one of the top venues for Chapter 11 filings in the United States. We have handled high-profile bankruptcy matters filed in Delaware, including traditional, pre-packaged, and pre-arranged restructuring and insolvency proceedings.
Our work encompasses numerous successful representations of lenders, investors, and industry-leading companies in sectors that range from real estate and hospitality to energy, healthcare, telecommunications, transportation, and retail. Many of these engagements are defined by a high level of complexity, often involving large-scale operations, billions of dollars of funded debt, intricate capital structures, international stakeholders, and adversary proceedings. Collaborating with colleagues in our Commercial Litigation and Appellate practices, we defend clients in complex lawsuits involving alleged fraudulent transfers, breaches of contract or fiduciary duty, alleged alter ego activity, and other commercial and bankruptcy causes of action.
Several of our restructuring and bankruptcy litigation matters filed in the Delaware courts have been recognized in publications including The American Lawyer, Turnarounds & Workouts, and Turnaround Management Association.
Experience
A selection of our recent experience includes:
Delaware M&A and Stockholder Actions
- Special Committee Deal Representation: Represented the Oracle directors in litigation concerning Oracle’s $9.3 billion acquisition of NetSuite that resulted in a complete defense victory. Through a variety of motions and other strategic moves, the Sidley team was able to obtain pre-trial dismissals for all of our clients with the exception of the Special Acquisition Committee’s chair, Ms. James, who proceeded to trial. Sidley served as her trial counsel and, following a 10-day trial, obtained a post-trial dismissal on behalf of Ms. James. The Court of Chancery then issued a post-trial decision in defendants’ favor, which was affirmed on appeal.
- Entire Fairness Dismissal: Achieved a rare dismissal of fiduciary claims subject to the onerous “entire fairness” standard of review on behalf of Hennessy Capital and the former directors of Hennessy Capital Acquisition Corp. IV, a Special Purpose Acquisition Company (SPAC). It was the first pleadings-stage dismissal in a case challenging a SPAC transaction under the so-called “entire fairness” doctrine.
- Busted Deal Litigation: Represented RoundPoint Mortgage Servicing Corp. and affiliates in an expedited trial in the Delaware Court of Chancery regarding its counterparty’s refusal to close a merger transaction. The matter resulted in the consummation of the transaction.
- M&A Litigation: Secured a sweeping trial victory for Brunswick Corporation in the Superior Court of Delaware. The Court ruled in favor of Brunswick on plaintiffs’ claims that Brunswick intentionally failed to disclose material facts and breached the parties’ Stock and Asset Purchase Agreement.
- Alternative Entity Litigation: Tried a significant and hard-fought Delaware corporate governance case in the Delaware Court of Chancery, representing Leo Investments Hong Kong Limited (Leo) as plaintiff in its dispute with Tomales Bay Capital (TBC), an investment adviser focusing on TBC’s 2021 ejection of Leo from an investment fund. In September 2025, the court issued its post-trial judgment, holding that the defendant breached its fiduciary duty of candor and granting Sidley’s client approximately $17 million in attorneys’ fees and expenses. Cross-appeals to the Delaware Supreme Court are currently pending.
- Advancement Litigation: Represented three C-suite executives in litigation in Delaware Court of Chancery asserting their rights to advancement and indemnification following the largest ever take-private transaction for a social media company. On an expedited basis, the Chancellor granted summary judgment for Sidley’s clients, upholding their rights and ordering payment of advancement.
- Special Committee Representation: Represented the Special Committee of the Board of Directors of Tesla in recommending that the shareholders should ratify Elon Musk’s 2018 compensation package, worth more than US$50 billion, and that Tesla should reincorporate in Texas. After extraordinary media coverage and commentary, shareholders overwhelmingly approved both measures, and all legal challenges were defeated.
Delaware Activism
- Enforcement of Activism Settlement Agreement: Achieved a Court of Chancery trial win and subsequent appellate affirmance on behalf of Texas Pacific Land Corporation (TPL), a public company, in a matter of first impression finding that the defendant investor group breached its contractual voting commitment and enabling the client to move forward with a critical component worth billions of dollars in potential new capital.
- Prevailing in Activism Dispute: Represented Purple Innovation, Inc. and a special committee of its board of directors in litigation filed in the Delaware Court of Chancery by Purple’s largest stockholder, alleging breaches of fiduciary duty in connection with an attempt by the stockholder to obtain control of the company and its board. The matter settled on the eve of trial, resulting in a very favorable agreement that precludes the stockholder from increasing its ownership or attempting to take control for two years — an uncommon concession for an activist investor.
- Prevailing in Advance Notice Bylaw Dispute: Secured an expedited trial win in the Court of Chancery for CytoDyn, Inc. in the first case in Delaware that addressed a board’s rejection of a nomination notice for failure to provide requested information pursuant to the company’s advance notice bylaw.
Actions in other jurisdictions drawing on Delaware law
- Defeating M&A Injunction: Prevailed before the U.S. District Court for the Western District of Washington by defeating an injunction sought by a stockholder plaintiff to enjoin the $6.25 billion take-private transaction of Nordstrom, Inc. (Nordstrom). Sidley represented a special committee of the Nordstrom board of directors in the deal process that led to the merger. The court’s rejection of the preliminary injunction enabled the company to proceed with a shareholder vote in which the merger was overwhelmingly approved by shareholders.
- Reversing M&A Injunction and Pursuing Damages Pursuant to Merger Agreement: Represented FUJIFILM Holdings Corporation at both the trial and appeals courts involving several litigation matters relating to a proposed, and then cancelled, merger with Xerox Corp. Achieved highly favorable settlement by which FUJIFILM bought out Xerox’s remaining interest in the joint venture and extracted numerous other concessions.
- Defeating Fiduciary Claims and Establishing New Law: Obtained a landmark decision from the New York Court of Appeals on behalf of the independent directors of Kenneth Cole Productions, Inc. In a matter of first impression, the Court of Appeals affirmed the New York Supreme Court and Appellate Division dismissal of class action claims for breach of fiduciary duty arising from the going-private transaction in which company founder Kenneth Cole purchased the outstanding shares of his eponymous fashion company.
- Prevailing in Advance Notice Bylaw Dispute: Served as lead counsel for HomeStreet, Inc. in a nationwide case of first impression, challenging an activist shareholder’s purported notice of director nominations and proposals as deficient under the company’s advance notice bylaw.
Complex Commercial Litigation
- Secured dismissal of all claims against Walgreens Boots Alliance regarding the $9 billion merger between VillageMD, a Walgreens subsidiary, and CityMD-Summit. The Delaware Court of Chancery dismissed the claims, and the Delaware Supreme Court affirmed.
- Helped obtain a significant appeal on behalf of Cantor Fitzgerald, L.P. in a closely watched case in the Delaware Supreme Court regarding the same forfeiture-for-competition provision of Cantor’s limited partnership agreement. On January 29, 2024, the Delaware Supreme Court reversed a ruling by the Chancery Court that invalidated these provisions of Cantor’s agreement. This highly anticipated decision should serve as important precedent in Delaware on several issues, including the enforceability of non-competitive conditions precedent to post-withdrawal payments.
- Represented Walgreens and its board of directors in litigation related to the now-defunct blood-testing company Theranos, including breach of contract litigation against Theranos, shareholder derivative litigation against the Walgreens Board, consumer class action litigation against Walgreens, and related government investigations and trials against Theranos’ executives. With respect to claims brought against the Walgreens Board, the Delaware Court of Chancery granted Sidley’s motion to dismiss, which was then affirmed by the Delaware Supreme Court.
- Secured a settlement for twice the amount originally sought on behalf of a prominent investment fund in a Delaware Court of Chancery dispute over an unpaid final distribution. During discovery, the Sidley team uncovered concealed funds and misconduct—including falsified evidence—leading the defendants to agree, shortly before trial, to pay double the claimed damages.
- Obtained a winning trial verdict on behalf of XRI Investment Holdings LLC against a former founder who fraudulently transferred his equity interests in violation of company agreement. Affirmed by the Delaware Supreme Court.
IP Litigation
- Successfully defended Nevro Corporation against Boston Scientific’s assertion of 20 patents and 60+ trade secrets over the course of six years of litigation in venues across the United States, including multiple Delaware cases. The litigations also included five Federal Circuit appeals, all of which were won by Nevro, and about 20 inter partes review proceedings, during which the majority of Boston Scientific’s patents were invalidated by Nevro. The lengthy litigation ended in August 2022 with Boston Scientific, the so-called plaintiff, paying Nevro US$85 million. Nevro considered these cases to be critical in protecting its innovative spinal cord stimulation technology and its market share.
- Represented Bayer in three patent cases against Baxalta and Nektar involving 14 patents relating to Factor VIII replacement therapy to treat hemophilia. In the first case, obtained a damages award of $182 million including interest that ranks among the 10 largest patent verdicts in the District of Delaware for the past decade. After a six-day jury trial involving 18 witnesses, the jury found in favor of Bayer across the board. The $182 million award was affirmed by the Federal Circuit.
- Successfully invalidated on behalf of Microsoft and HP three of four remote storage patents asserted by SynKloud in the District of Delaware under 35 U.S.C. § 101 on motions to dismiss. The case was settled shortly thereafter.
- Represented Peddinghaus Corporation in a patent case brought in the U.S. District Court for the District of Delaware by its competitor, Ficep Corporation, alleging infringement of a patent regarding automation of manufacturing processes. On February 28, 2022, the Court granted Peddinghaus’ motion for summary judgment on the grounds that Ficep’s patent was directed to a patent-ineligible abstract idea. Ficep appealed the invalidity determination to the U.S. Court of Appeals for the Federal Circuit. On August 21, 2023, Sidley obtained a complete victory from the Federal Circuit in favor of Peddinghaus.
Bankruptcy and Insolvency Litigation
- Successfully represented Glocal Healthcare Systems Private Limited, an Indian digital healthcare company, in a multi-jurisdictional dispute related to a de-SPAC transaction with parallel actions before the U.S. Bankruptcy Court for the District of Delaware, the Seventh Circuit, and various courts in India. Sidley obtained a highly favorable settlement within a month of being retained, resulting in a net gain in value for Glocal of US$27.5 million.
- Representing an ad hoc group of noteholders with over US$2 billion of first-lien obligations and debtor-in-possession (DIP) loans issued by Ligado Networks LLC, a mobile communications company that operates a satellite network across North America, in connection with Ligado’s prearranged Chapter 11 cases in the U.S. Bankruptcy Court for the District of Delaware.
- Represented the prepetition ABL Agent in the Chapter 11 bankruptcy cases of Number Holdings, Inc., the parent company of 99 Cents Only Stores LLC, which was a discount retail store. Sidley guided the ABL Agent and ABL lenders through the prepetition and bankruptcy process, ultimately resulting in a very successful outcome – payment in full of the ABL lenders well in advance of the plan confirmation process.
- Successfully led the Chapter 11 cases for Casa Systems, Inc., a telecommunications hardware and software company with approximately US$183 million in funded debt and operations across more than 10 countries at the time of filing, culminating with the fully consensual, uncontested confirmation of its Chapter 11 plan in the U.S. Bankruptcy Court for the District of Delaware on June 5, 2024. Turnarounds & Workouts featured this matter on its “Largest Chapter 11 Bankruptcy Cases of 2024” list.
- Successfully guided Anthelion Capital Holdings through the acquisition of the Energy business unit of integrated electric bus and commercial vehicle power train manufacturer Proterra Inc., pursuant to Proterra’s Chapter 11 plan of reorganization in the U.S. Bankruptcy Court for the District of Delaware. Under Proterra’s confirmed Chapter 11 plan, the full amount of Anthelion Capital’s loan, less the purchase price for the Energy business unit, was repaid in cash.
- Represented OYA Renewables Development LLC, a Boston- and Toronto-based solar power infrastructure developer, and seven of its affiliates in their Chapter 11 restructuring in the U.S. Bankruptcy Court for the District of Delaware. The court approved OYA’s Chapter 11 plan on a fully consensual basis, and Turnarounds & Workouts featured this matter on its “Largest Chapter 11 Bankruptcy Cases of 2024” list.
*Sidley associated with Delaware counsel in these matters.
