Offshore support and Asia-Pacific exploration dominated sector news, with Gulf Marine Services confirming a customer's decision to extend an existing vessel deployment in the Gulf, while Sunda Energy reported a sharply upgraded resource estimate at its Philippines exploration prospect. Both stocks nudged higher on the news, though neither move reflects a step-change in near-term revenue.
Gulf Marine Services secures one-year vessel extension
Gulf Marine Services (LSE:GMS), which provides self-propelled, self-elevating support vessels to the offshore energy sector, has received confirmation from a major National Oil Company customer that it will exercise a one-year contract option covering one of the group's Small-class vessels operating in the Gulf Cooperation Council region. The shares ticked up 0.55% to 18.3p on the news, part of a fleet business whose investment case is built on long-term utilisation across the Middle East and beyond.
The option applies to a vessel deployed in the client's offshore maintenance operations, with all existing terms and conditions carrying over unchanged for the extended period. The arrangement traces back to the original contract disclosed on 3 November 2022, which included this option from the outset, meaning the extension confirms a pre-agreed continuation rather than introducing new commercial terms. GMS operates a fleet of 15 self-elevating support vessels split into Small, Mid and Large classes, deployed across platform maintenance, well intervention and offshore wind turbine work in the region.
"This option exercise is a strong endorsement of the reliability and value GMS brings to its clients' offshore operations," said Mansour Al Alami, Executive Chairman of GMS.
The extension does not expand GMS's fleet, revenue base or backlog, the vessel continues at its existing day rate under terms fixed nearly four years ago. What it does reinforce is customer retention in a region where repeat business from National Oil Companies underpins forward visibility. With the company's broader story resting on its roughly $659 million backlog and execution of a four-year Brazil deployment, this renewal is best read as a steady, low-drama data point confirming operational reliability rather than a catalyst for re-rating the stock.
Sunda Energy prospect estimate pitched at 3Tcf net
Sunda Energy (AIM:SNDA), the exploration and appraisal company focused on Asia-Pacific hydrocarbon assets, said operator Tetragon Energy has raised Mid Case Prospective Resources for the Halcon prospect to 8.0 trillion cubic feet gross, equivalent to 3.0 Tcf net to Sunda's stake, with a geological chance of success of 24%. The shares rose 1.7% to 3.0p as the market digested the upgraded figures. Halcon sits within Philippines Service Contract 80, part of an offshore position in the Bangsamoro Autonomous Region of Muslim Mindanao operated by Tetragon alongside Sunda (37.5%), PXP Energy Corporation (12.5%) and The Philodrill Corporation (12.5%).
The revised estimate supersedes a prior figure for Halcon and four other key SC 80 prospects that Sunda disclosed on 8 October 2025, which had been based on a 2015 competent person report prepared by Mitra Energy The gap between the decade-old technical work and Tetragon's new assessment points to a substantially reappraised subsurface picture at Halcon specifically.
A near-tripling in disclosed resource size at a single prospect, even on an unrisked Mid Case basis, materially strengthens the scale argument for Sunda's SC 80 exposure ahead of any drilling decision. The 24% chance of success keeps this firmly in exploration-risk territory, but the upgrade gives Sunda a larger prize to point to as it and its partners weigh next steps on the block.