Explicit Waiver of Sovereign Immunity in International Guarantees Under FSIA

Introduction

Williams v. Federal Government of Nigeria, decided by the United States Court of Appeals for the Second Circuit on April 9, 2025, clarifies the standard for how and when a foreign state can be stripped of sovereign immunity under the Foreign Sovereign Immunities Act (FSIA). The dispute arose after Dr. Louis Emovbira Williams obtained a default judgment in the United Kingdom against Nigeria for breach of a 1993 instrument called the “Fidelity Guarantee and Abiding Memorandum of Understanding of Assurance.” When Nigeria refused to pay, Williams sued in New York state court. Nigeria removed the case to federal court and sought dismissal on sovereign‐immunity grounds. The district court—and now the Second Circuit—held that Nigeria had “explicitly” waived immunity in the Fidelity Guarantee. This decision cements a new principle: a clear and unambiguous forum‐selection or immunity‐waiver clause in an international instrument binds a foreign state in U.S. courts, even if the document does not name the United States specifically.

Summary of the Judgment

The Second Circuit affirmed the district court’s order denying Nigeria’s motion to dismiss for lack of subject matter jurisdiction under the FSIA. Applying the collateral‐order doctrine, the appellate court reviewed de novo the legal question of waiver and for clear error any factual findings. The court held:

The Fidelity Guarantee’s paragraph 21 contains language permitting Williams to select “any country” to enforce the award and unequivocally waiving “acts of state, state privileges, state secrecy and state immunities” without doubt.
Under Capital Ventures International v. Republic of Argentina, waiver language referring to “any court” suffices to waive immunity in U.S. courts.
Additional provisions (paras. 18 and 20) reinforce that Nigeria waived all jurisdictional defenses, including immunity from execution.
The 2018 U.K. judgment declined to treat the Guarantee as an agreement by Nigeria itself to submit to U.K. jurisdiction, but that issue differed materially from the waiver question under the FSIA. Consequently, the U.K. decision did not preclude the U.S. court from finding an explicit waiver.

The court therefore held that Nigeria is not immune, and Williams may proceed to enforce his judgment in U.S. courts.

Analysis

Precedents Cited

Capital Ventures International v. Republic of Argentina (552 F.3d 289, 2d Cir. 2009): Established that waiver language referring to “any court” or “any jurisdiction” is a clear and unambiguous waiver of sovereign immunity under FSIA §1605(a)(1), even if the United States is not named explicitly.
Arch Trading Corp. v. Republic of Ecuador (839 F.3d 193, 2d Cir. 2016): Confirmed that courts may consider materials beyond the complaint to resolve jurisdictional questions under the FSIA.
Kensington International Ltd. v. Itoua (505 F.3d 147, 2d Cir. 2007): Held that a foreign state must “opt in” to U.S. jurisdiction through clear waiver language.
Pablo Star Ltd. v. Welsh Government (961 F.3d 555, 2d Cir. 2020): Recognized that denials of immunity under the FSIA are immediately appealable collateral orders.
Republic of Ecuador v. Chevron Corp. (638 F.3d 384, 2d Cir. 2011): Outlined the four‐part test for issue preclusion under federal law.

Legal Reasoning

The court’s opinion pivots on FSIA §1605(a)(1), which provides that a foreign state “shall not be immune” if it has “waived its immunity either explicitly or by implication.” The Second Circuit has defined “explicit” waiver as language that is “clear and unambiguous.” Paragraph 21 of the Fidelity Guarantee permits Williams to sue “in the UK or Nigeria or any other country” and expressly waives “acts of state,” “state immunities,” and related defenses “without any equivocation and doubt whatsoever.” Paragraphs 18 and 20 reinforce that waiver by forbidding objections on immunities grounds and permitting execution against Nigerian State assets. These provisions satisfy the explicit‐waiver standard set by Capital Ventures.

Nigeria’s argument that a prior U.K. court ruling rejected waiver was rebuffed. Under collateral estoppel, a party must show that the exact same issue was decided in the prior proceeding. The U.K. court analyzed whether Nigeria, as a sovereign party, had agreed to U.K. jurisdiction in the contract, whereas the FSIA question is whether broad waiver language unambiguously covers U.S. courts. Because the issues were not identical, the U.K. decision did not bind the U.S. court’s jurisdictional analysis.

Impact

Williams v. Federal Government of Nigeria has immediate and far‐reaching consequences:

Contract Drafting: States and state‐owned entities must be cautious when agreeing to broad jurisdictional or immunity‐waiver clauses. Even a general waiver of “any immunity” or selection of “any forum” may expose them to suit in U.S. courts under FSIA.
Forum Selection Litigation: Plaintiffs seeking to enforce international judgments or settlement awards will look closely for explicit waiver language to defeat sovereign immunity defenses.
Judicial Interpretation: Lower courts in the Second Circuit—and potentially elsewhere—will apply this decision to scrutinize foreign‐state contracts for clarity of waiver, reinforcing a pro‐jurisdictional reading when waiver language is unequivocal.
International Comity: This case underscores that U.S. courts will enforce clear waiver commitments, even if other jurisdictions interpret the same document differently.

Complex Concepts Simplified

Sovereign Immunity: A doctrine preventing a foreign state from being sued in another country’s courts, unless the state consents or an exception applies.
Foreign Sovereign Immunities Act (FSIA): U.S. statute that codifies when and how foreign states can be sued in U.S. federal and state courts, including waiver and commercial‐activity exceptions.
Explicit Waiver: A clear, unambiguous statement by a sovereign that it agrees to be sued, removing its immunity.
Collateral Order Doctrine: Permits immediate appeals from a district court’s denial of immunity, even before final judgment on the merits.
Issue Preclusion (Collateral Estoppel): Bars relitigation of an identical issue decided in a prior suit, but only if the issues and parties are the same.

Conclusion

Williams v. Federal Government of Nigeria establishes a clear rule: when a foreign‐state contract contains unambiguous language waiving “any immunities” or permitting suit “in any forum,” that instrument constitutes an explicit waiver under FSIA §1605(a)(1). The Second Circuit’s decision reaffirms the importance of precise drafting in international agreements and provides litigants a powerful tool to overcome sovereign immunity defenses. As a new precedent, Williams will shape enforcement actions, contract negotiations, and jurisdictional disputes for years to come.