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    Home /  About /  News and Events /  Client Highlights
    Client Highlights

    Appellate Preeminence: S&C’s Recent Victories for FirstEnergy, Republic of Argentina, and Others Are Reshaping the Law

    • Related Practices
    August 27, 2025

    In recent months, S&C has delivered a series of appellate wins in high-stakes cases before the U.S. Supreme Court and circuit courts that have addressed issues ranging from the standards for class certification, attorney-client privilege, protections for foreign sovereignty, standing to sue over federal regulations, and the reach of administrative rules post-Chevron. Many were achieved in extraordinary situations, including interlocutory appeals and mandamus petitions.

    For FirstEnergy, one of the country’s largest investor-owned utilities, we obtained two critical rulings in the space of one week in August that defused massive securities litigation arising from a high-profile public corruption scandal. First, we obtained a Sixth Circuit stay on a mandamus petition, halting a district court order in a securities class action that would have granted plaintiffs access to FirstEnergy’s internal investigations. Then we obtained a Sixth Circuit ruling vacating the certification of that class of investors seeking billions of dollars in the wake of the scandal.

    High stakes were also at play for the Republic of Argentina. The Republic faced a U.S. district court order requiring it to turn over its 51 percent stake in YPF, the largest Argentine energy company, to partially satisfy a $16.1 billion judgment. We persuaded the Second Circuit in August to stay the order, which threatened to upend long-established principles of sovereign immunity, destabilize YPF, and harm the Argentine economy. S&C is also representing the Republic in its appeal of the underlying judgment.

    Just this calendar year, we have also obtained appellate victories for:

    • A Valero subsidiary, persuading the U.S. Supreme Court in Diamond Alternative Energy v. EPA to reverse in an important standing case that will allow affected parties to challenge government rules.
    • Walgreens, obtaining a victory in a landmark bellwether case in the national opioid multidistrict litigation, with the Ohio Supreme Court and Sixth Circuit invalidating a $650 million judgment obtained by two Ohio counties.
    • Broadband industry groups, ending two decades of fighting and uncertainty over broadband regulation by persuading a unanimous Sixth Circuit to strike down the FCC’s controversial net-neutrality rules.
    • The Republic of Argentina, obtaining a Second Circuit ruling affirming the dismissal of claims that the country owes more than $650 million to hedge funds that had speculated on certain of its securities.
    • Standard Chartered Bank and Danske Banke, persuading the Second Circuit that the banks are not liable under the Anti-Terrorism Act for allegedly aiding and abetting terrorist organizations.
    • CPI Security Systems, Inc., defending a $189.7 million verdict, including $140 million in punitive damages, that it won against a much larger competitor, Vivint, for unfair and deceptive business practices.
    • The National Association of Private Fund Managers, Managed Funds Association and Alternative Investment Management Association in a successful Fifth Circuit challenge to two SEC rules requiring public disclosure of short-sale activity and securities loans.
    • Canadian Pacific following its $31 billion acquisition of Kansas City Southern, defeating a breach of contract suit brought by investors holding $2.4 billion of notes, and persuading the D.C. Circuit to reject a petition from Chicago suburbs challenging the approval of the merger.
    • Spirit AeroSystems in a second appellate victory in the Tenth Circuit in a case involving compensation for the company’s former CEO.
    • Sumitomo entities, obtaining a reversal from a New York appellate court in litigation over a contractual tax-allocation provision in a $2.2 billion M&A deal.

    Our Supreme Court and Appellate team is one of the most sought-after in the country. In addition to handling challenging and high-profile appeals, we provide counseling on complex legal issues at early stages of litigation or before litigation even begins. And as many of these wins illustrate, we are particularly adept at creative appellate strategies for clients’ most important matters, including seeking case-altering interim relief.

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