Form 8-K Filing by Flutter Entertainment plc

Flutter Entertainment plc (the "Company") filed a Form 8-K on December 23, 2025, to report the submission of a Standard Form TR-1 (Standard Form for Notification of Major Holdings). This notification was made in compliance with the United Kingdom Financial Conduct Authority's Disclosure Guidance and Transparency Rules. The filing includes an RNS Announcement dated December 23, 2025, as Exhibit 99.1, detailing the major holdings notification. The RNS Announcement itself, Exhibit 99.1, provides information regarding BlackRock, Inc.'s holdings in Flutter Entertainment. It states that on December 19, 2025, BlackRock, Inc. crossed or reached a notification threshold, with the issuer being notified on December 22, 2025. The filing details BlackRock's voting rights and financial instruments, indicating that the total percentage of voting rights held by BlackRock, Inc. after the event was below 5%. The document also lists a complex chain of controlled undertakings through which BlackRock, Inc. effectively holds its voting rights and financial instruments.