Acreage Expansion Around Temaris Cluster PSC

Seascape Energy, an E&P company focused on Southeast Asia, is pleased to announce that it has received a Letter of Agreement from PETRONAS via Malaysia Petroleum Management ("MPM") in respect of a large areal extension to the north and east of its Temaris Cluster Small Field Asset PSC (Seascape 100%) ("Temaris Area Extension", together the "Temaris PSC").

Highlights

• Increases the Temaris SFA PSC to ~1,770 sq km, a 45% uplift in the overall PSC area
• Potential to double the existing ~1 TCF of net mean Prospective Resources currently identified on the Temaris PSC with an updated independent CPR recently commissioned
• Seascape will benefit from new 3D seismic data being acquired by PETRONAS in late 2026 over the Temaris Area Extension as part of a regional programme
• Ensures all resources are monetised under the same, enhanced SFA PSC fiscal terms
• Minimal additional firm work commitment funded from existing cash resources
• As previously announced, the process has restarted to introduce a strategic partner into the Temaris PSC

The Temaris Area Extension covers the continuation of the Temaris channelised Miocene sandstone system and allows Seascape to pursue this extensive play under a single, continuous PSC and remains subject to the execution of final documentation.

Background

The Temaris PSC was awarded 100% to Seascape Energy in June 2025 as part of the Discovered Resource Opportunity element of MBR 2025. Temaris is comprised of two gas discoveries and significant exploration potential in shallow water (~70 metres) offshore Peninsular Malaysia on the western flank of the Malay basin covering an original area of approximately 1,200 sq km.

Following award, Seascape undertook an extensive subsurface review of Temaris and the surrounding area and completed a 3D seismic reprocessing project, utilising high-end Full Waveform Inversion techniques.

This work resulted in the identification of a significant extension of the high-quality, Miocene channelised sandstone play proven by the Tembakau and Mengkuang gas discoveries. These channel features exhibit a strong seismic amplitude response when gas-charged and are evident across the newly enlarged Temaris PSC in multiple horizons.

Broadening the Portfolio, Deepening the Prospect Inventory

Recognising the importance of pursuing these significant resources under a single, unified PSC, PETRONAS has granted Seascape a 547 sq km Temaris Area Extension, increasing the total Temaris PSC area to approximately 1,770 sq km, a 45% uplift.

Importantly, based on extensive subsurface work by the Company over the past year, the Temaris Area Extension is anticipated to result in a significant increase in the exploration upside on block. Seascape has commissioned Sproule ERCE to undertake an update to the original CPR which had already identified 950 bcf of gross mean Prospective Resources on the Temaris PSC across a number of trapping styles and horizons. The updated report is anticipated to be published in Q4 2026.

The Temaris Area Extension will enable the Company to capture the entire, extensive gas play as part of its area-wide development plan which includes the flexibility to rapidly monetise any incremental discoveries in the area.

Seascape has also been informed by PETRONAS that it intends to make available to the Company the new 3D seismic data covering the Temaris Area Extension. It is anticipated this data will de-risk a possible extension of the Mengkuang discovery (2C: 29 bcf), identified by Seascape on legacy 2D data.

The additional work commitment to the Temaris Area Extension will include the processing of the new 3D seismic and the drilling of a contingent exploration well in the area. The firm financial commitment will be met through Seascape's existing cash resources and the Temaris Area Extension remains subject to the execution of final documentation.

Temaris Strategic Partner Update

Given the significance and confidential nature of the Temaris Area Extension, Seascape previously made the decision to pause the process to introduce a strategic partner into the Temaris PSC ensuring value is maximised for stakeholders from this extensive area.

Seascape has now restarted the Temaris farm-out process with the benefit of the enlarged prospectivity, a rapidly maturing field development plan ("FDAP") and a supportive macro environment.

The Company continues to receive strong interest in the process for this uniquely positioned asset in a geographically advantaged location and Seascape's ambition is to introduce a high-quality partner into the Temaris PSC prior to FDAP submission in late Q4 2026.

Pierre Eliet, Malaysia Country Chair and Executive Director, commented:

"This is a welcome portfolio addition at a time when macro events are leading the industry to re-think its strategic priorities. The value of Asian gas into Asian markets is starting to become clear, and the attractions of scarce, high-quality exploration opportunities in stable jurisdictions with strong, high-growth, high demand markets is becoming very apparent.

This acreage expansion enhances the value of our Temaris asset, capturing more of the play and adding breadth and depth to our prospect inventory. It also demonstrates the belief the regulator has in Seascape to continue to develop the technical understanding of the play and its confidence in the Company as an operator in the Malay basin."

Enquiries: Seascape Energy Asia plc IR@seascape-energy.com Nick Ingrassia (Chief Executive) Pierre Eliet (Executive Director) Stifel (Nomad and Joint Broker) Tel: +44 20 7710 7600 Callum Stewart Simon Mensley Ashton Clanfield SNELSeascape@Stifel.com Cavendish Capital Markets Limited (Joint Broker) Tel: +44 20 7397 8900 Neil McDonald Pete Lynch

Standard

Review by Qualified Person

Glossary

"2C Contingent Resources" means those quantities of petroleum estimated, as of a given date, to be potentially recoverable from known accumulations by application of development projects but which are not currently considered to be commercially recoverable due to one or more contingencies. Contingent resources are a class of discovered recoverable resources

"bcf" means billion standard cubic feet

"CPR" means a Competent Person's Report

"FDAP" means Field Development and Abandonment Plan

"m" means metres

"mmboe" means million barrels of oil equivalent

"MBR" means Malaysian Bid Round

"Prospective Resources" means estimated potentially discoverable resources

"PSC" means Production Sharing Contract

"SFA" means Small Field Asset

"sq km" means square kilometres

"TCF" means trillion standard cubic feet