Southeast Asia's sellers have put US$9.6 billion of upstream assets on offer for the remainder of this year and 2027, according to research from Rystad Energy, as the region's M&A cycle turns from non-core exits by international oil companies (IOCs) to strategic entry by buyers.

The figure marks a competitive new phase. Roughly US$6.7 billion in upstream assets changed hands in 2025 under that new intent — a break from 2020-2024, when majors trimming late-life positions and expiring production sharing contracts (PSCs) dominated the deal flow.

How much are buyers paying?

Transaction metrics have climbed with the competition. Recent deals have reached US$9.8 per barrel of oil equivalent (boe) for development assets and over US$3/boe for pre-final investment decision (FID) resources, Rystad data show. Those levels compare with six-year averages of US$6-7/boe and US$1.5/boe, respectively.

The premium gap — nearly 40% above trend for development assets and double the long-run price for pre-FID resources — signals that buyers are underwriting growth, not just harvesting decline profiles.

Who is selling, and why?

The US$9.6 billion on offer splits almost evenly between majors (US$3.6 billion) and independents (US$3.7 billion). National oil companies (NOCs) account for US$1.4 billion, with a handful of smaller sellers making up the rest.

Each group is selling for different reasons:

• Majors are divesting in countries with limited upside to concentrate on a few core basins, and entering frontier acreage through partnerships rather than carrying risk alone.
• Independents, holding recent pre-FID discoveries such as Harbor Energy's Andaman portfolio, need capital beyond a single balance sheet to reach FID.
• NOCs are the most selective, having built domestic portfolios — Petronas through its Searah joint venture with Eni, for example — which now lets them rationalise late-life assets at home while eyeing entry elsewhere.

What shapes the next 18 months?

Prateek Pandey, Head of APAC Oil & Gas Research at Rystad Energy, framed the outlook in a single theme.

"Growth is the common theme across nearly every portfolio in the region right now. The next 18 months will be shaped by three things: the conversion of pre-FID opportunities into mega M&A deals, the trajectory of premiums on producing assets, and the continued evolution of deal structures into strategic partnerships," Pandey said.

He added a caution for bidders: "For buyers, capital alone won't win the next round. The premium a bidder can justify will come down to the value creation plan behind the offer."

The watch items

Three variables will decide whether the US$9.6 billion clears at current metrics: whether pre-FID discoveries convert into the mega-deals Pandey expects, whether development-asset premiums hold above US$9/boe, and how far deal structures migrate toward partnership models that spread frontier risk. For sellers with maturing PSCs, the entry of growth-minded buyers offers an exit window that the exit-driven market of 2020-2024 never did.