Commencement of ITLOS Hearing

10 November 2026

Rockhopper Exploration plc

("Rockhopper", the "Group" or the "Company")

Commencement of ITLOS Hearing

Rockhopper Exploration plc (AIM: RKH), the oil and gas company with key interests in the North Falkland Basin, notes that the International Tribunal for the Law of the Sea (“ITLOS”) hearing considering Argentina's request for provisional measures under the United Nations Convention on the Law of the Sea is commencing in Hamburg today (the “Tribunal”).  The hearing is scheduled for two days with judgment expected prior to the end of the year.

The Tribunal hearing is a State to State matter between the United Kingdom and Argentina. A further update, including implications, if any, for the Company’s Sea Lion project will be provided as and when appropriate.

Further details can be found at https://www.itlos.org/en/main/cases/case-concerning-hydrocarbon-exploitation-in-the-south-west-atlantic-ocean-argentina-v-united-kingdom-provisional-measures/

Enquiries:

Rockhopper Exploration plc

Sam Moody - Chief Executive Officer

Tel. +44 (0) 20 7390 0234 (via Vigo Consulting)

Canaccord Genuity Limited (NOMAD and Joint Broker)

Henry Fitzgerald-O'Connor/Charlie Hammond

Tel. +44 (0) 20 7523 8000

Peel Hunt LLP (Joint Broker)

Richard Crichton/Georgia Langoulant

Tel. +44 (0) 20 7418 8900

Vigo Consulting

Patrick d'Ancona/Ben Simons/Fiona Hetherington

Tel. +44 (0) 20 7390 0234

Notes to Editors

Rockhopper Exploration plc is a UK-based oil and gas exploration and production company with key interests in the Falkland Islands. The Company holds a 35% interest in licences in the North Falkland Basin, where it has sanctioned the development of the significant Sea Lion field which was originally discovered by the Company in 2010.

Rockhopper's shares are quoted on the AIM market of the London Stock Exchange under the ticker RKH.

For more information, visit the Company's website at www.rockhopperexploration.co.uk.