Mercuria Energy Group Limited v. Republic of Poland — D.C. Cir. (Sep 30, 2026)

No. 25-7152 Argued September 30, 2026 Published October 2, 2026

The D.C. Circuit hears Mercuria Energy Group Limited's effort to enforce an arbitration award against Poland. Poland fined Mercuria's fuel-trading subsidiary for allegedly failing to maintain required fuel stocks. Polish courts overturned the fine. Poland refunded the penalty, but a dispute over interest remained. Mercuria took that dispute to arbitration under the Energy Charter Treaty and won an award. Sweden was the legal seat; lex arbitri means the law governing the arbitration process. A Swedish court then invalidated the award under European Union rules restricting arbitration between EU states and investors from other EU states. An American district judge refused to enforce it. Mercuria will contend that honoring the annulment would deny basic justice. Poland will defend the Swedish ruling and the narrow limits on enforcing an annulled award.

Mercuria Energy Group Limited v. Republic of Poland (No. 25-7152) — U.S. Court of Appeals for the D.C. Circuit, argued September 30, 2026.

Sources

Argument audio — D.C. Circuit (public domain, 17 U.S.C. § 105):https://media.cadc.uscourts.gov/recordings/docs/2026/09/25-7152.mp3

Argument date and case listing — D.C. Circuit:https://media.cadc.uscourts.gov/recordings/bydate/2026/9

Enforcement opinion — D.D.C., September 8, 2025, Doc. 47 (actual court PDF, public reproduction):https://italaw.com/sites/default/files/case-documents/italaw1827087.pdf

Underlying events and arbitral award — SCC V 2019/126, December 29, 2022 (actual award PDF):https://www.italaw.com/sites/default/files/case-documents/italaw171104.pdf

Law of the Swedish arbitration seat — Swedish Arbitration Act, §§ 43 and 46 (SCC English translation; Swedish text is authoritative):https://sccarbitrationinstitute.se/wp-content/uploads/2026/08/Swedish-Arbitration-Act.pdf

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