Guyana: Forty-Five Per Cent of the Best Barrel Found This CenturyWide moat

ExxonMobil (XOM) — moat facet

A discovery in 2015 is 900,000 barrels a day in 2025, and it is the reason one half of Upstream earns 17.7 per cent while the other earns 4.3.

The Stabroek block off Guyana is the reason ExxonMobil's non-US Upstream earns 17.7 per cent on capital while its American Upstream earns 4.31. It is also the clearest case in the company of an advantage that was created rather than purchased.

Upstream earnings, second quarter ($m)$1,212mU.S. 2025$1,920mU.S. 2026$4,190mNon-U.S. 2025$6,007mNon-U.S. 2026ExxonMobil Form 10-Q, quarter to 30 June 2026; advantaged volume, mainly Guyana and Permian, added $1,140m
Non-U.S. Upstream, where Guyana sits, earned three times the U.S. in the quarter.

The sequence is short for an industry that measures itself in decades. First oil came in 2019. By 2025 the fourth development, Yellowtail, had started up on the ONE GUYANA vessel, taking installed capacity on the block above 900,000 barrels a day, and it ramped to roughly 250,000 barrels a day within three months2. Uaru and Whiptail are in development, Hammerhead was funded in 2025 for a 2029 start, and ExxonMobil expects eight production vessels on Stabroek by the end of 20303. Guyana is most of why total company production rose from 3,738 thousand oil-equivalent barrels a day in 2023 to 4,736 in 20254.

What makes these barrels valuable is not only their cost but their shape. Deepwater production from a purpose-built vessel declines slowly and runs at high rates for years, which is the opposite of a shale well. And the block is governed by a petroleum agreement rather than a lease: the Petroleum Activities Act 2023 provides for production periods of twenty years for an oil field with renewal of up to ten more5. That is a long, defined term on the best asset the company has.

ExxonMobil holds 45 per cent and operates. CNOOC holds 25 per cent. The remaining 30 per cent belonged to Hess and, since July 2025, belongs to Chevron6. ExxonMobil went to arbitration to stop that and lost, which is the subject of its own page here — but the relevant point for the moat is that operatorship, not equity, is what confers the advantage. ExxonMobil decides the development sequence, the vessel design and the drilling programme, and takes the fee for doing it.

The risk is stated in the same sentence as the reward. A twenty-year production period is granted by a government whose national budget is now dominated by this one block, in a country that had no oil industry a decade ago and has a border dispute with Venezuela over the territory the block sits beside.

Watch installed capacity against actual production. Capacity above 900,000 barrels a day and a target of roughly 1.3 million once Whiptail arrives is only worth what the vessels actually lift, and Guyana's history so far is of production running ahead of the nameplate rather than behind it.

Moat trajectory: Widening

Four developments producing, capacity above 900,000 barrels a day, and eight vessels expected on the block by the end of 2030. Guyana is the highest-return barrel ExxonMobil has and the one it found rather than bought. The risks are fiscal and geopolitical rather than geological, and neither has materialised.

The number that tests this moat
Reported
Stabroek installed capacity
above 900,000 barrels a day

Four developments producing after Yellowtail started up on the ONE GUYANA vessel in 2025, heading toward roughly 1.3 million once Whiptail arrives and eight vessels by the end of 2030. ExxonMobil holds 45% and operates. Watch actual production against installed capacity; Guyana has so far run ahead of nameplate.

Source: ExxonMobil Guyana news release, August 2025 ↗
⚠ Threats to the moat
⚠ THREAT 01
The Contract Is Written by One Government
Twenty years of production rights, granted by a government whose budget now depends on them, in territory a neighbour claims.
References
  1. ReportedThe Stabroek block off Guyana is the reason ExxonMobil's non-US Upstream earns 17.7 per cent on capital while its American Upstream earns 4.3.
    Exxon Mobil Corporation Form 10-K for FY2025, Business Profile (Financial) — earnings after income taxes, average capital employed, return on average capital employed and cash capital expenditures for each segment and geography, and the corporate total. — FY2025 · publ. February 2026 · source ↗
  2. ReportedBy 2025 the fourth development, Yellowtail, had started up on the ONE GUYANA vessel, taking installed capacity on the block above 900,000 barrels a day, and it ramped to roughly 250,000 barrels a day within three months.
    ExxonMobil news release, 'ExxonMobil Guyana begins production at fourth offshore Guyana project' — start-up of the Yellowtail development on the ONE GUYANA floating production, storage and offloading vessel, taking installed capacity on the Stabroek block above 900,000 barrels of oil per day, and the subsequent ramp toward 250,000 barrels a day. — August 2025 · publ. 8 August 2025 · source ↗
  3. ReportedUaru and Whiptail are in development, Hammerhead was funded in 2025 for a 2029 start, and ExxonMobil expects eight production vessels on Stabroek by the end of 2030.
    Exxon Mobil Corporation Form 10-K for FY2025, Management's Discussion and Analysis — Business Results: segment financial results and identified items, the 2025 earnings driver analyses for each segment, and the Upstream highlights covering the Permian, Guyana, LNG and the major project portfolio. — FY2025 · publ. February 2026 · source ↗
  4. ReportedGuyana is most of why total company production rose from 3,738 thousand oil-equivalent barrels a day in 2023 to 4,736 in 2025.
    Exxon Mobil Corporation Form 10-K for FY2025, Items 1 and 2 — Business and Properties: oil and gas production and reserves tables, wells drilling, the review of principal ongoing activities by region (United States, Canada/Other Americas incl. Guyana and Brazil, Europe, Africa, Asia, Australia/Oceania), lease and production-sharing terms including the Guyana Petroleum Activities Act 2023, employees, and the list of lower-emission and new business opportunities. — FY2025 · publ. February 2026 · source ↗
  5. ReportedAnd the block is governed by a petroleum agreement rather than a lease: the Petroleum Activities Act 2023 provides for production periods of twenty years for an oil field with renewal of up to ten more.
    Exxon Mobil Corporation Form 10-K for FY2025, Items 1 and 2 — Business and Properties: oil and gas production and reserves tables, wells drilling, the review of principal ongoing activities by region (United States, Canada/Other Americas incl. Guyana and Brazil, Europe, Africa, Asia, Australia/Oceania), lease and production-sharing terms including the Guyana Petroleum Activities Act 2023, employees, and the list of lower-emission and new business opportunities. — FY2025 · publ. February 2026 · source ↗
  6. ReportedThe remaining 30 per cent belonged to Hess and, since July 2025, belongs to Chevron.
    CNBC, 'Chevron defeats Exxon in dispute over Guyana oil assets, clearing path for Hess acquisition' — the arbitration over the right of first refusal on Hess's 30% interest in the Stabroek block, ExxonMobil's 45% operated interest and CNOOC's 25%, and the completion of Chevron's $53 billion acquisition of Hess. — July 2025 · publ. 18 July 2025 · source ↗
Sources
Generated September 23, 2026