On Tuesday, June 9, 2026, ExxonMobil Guyana Limited declined to address public questions surrounding its proposed nominee for a neutral sole expert tasked with resolving a long-running $214 million cost oil dispute tied to exploration activities between 1999 and 2017, while openly signaling the deadlocked issue may soon head to international arbitration.
The disagreement first emerged in 2019, when a formal audit conducted by UK-based industry firm IHS Markit found major irregularities in the claimed costs: $34.34 million of the total claims were deemed ineligible for classification as cost oil, and a further $180 million lacked any supporting documentation to back up the expenditures. Industry sources familiar with the negotiations confirmed that ExxonMobil has repeatedly pushed for its own preferred candidate to oversee the resolution process, despite the dispute entering its seventh year of stalled talks with the Guyanese government.
During a press briefing Tuesday, John Cullen, ExxonMobil Guyana’s Vice President and Business Services Manager, dodged direct questions asking whether conflict of interest concerns over the company’s chosen nominee is one of the core obstacles to reaching a negotiated resolution. Cullen only outlined general criteria for the role, noting that any selected sole expert is required to meet a set of pre-agreed qualifications acceptable to both parties. “Objectivity is one of them. That is one of the criteria that we are discussing with the government, as well as experience, relevant experience, which is another key factor,” he told reporters.
Cullen sidestepped multiple follow-up inquiries about the impasse over selecting the expert, stating only that the company and the Guyanese government are continuing to work “very diligently” to identify a candidate that all sides can agree on. Despite this, he openly hinted that arbitration at the Paris-based International Chamber of Commerce (ICC) is the most likely next step if the deadlock persists. “If we’re unable to arrive at a mutual selection, that can be referred to the ICC to make the selection, which very well may be the next step in the process,” Cullen said.
The Guyana Revenue Authority (GRA), the South American nation’s national tax body, has already taken a hard line on the dispute, ruling out any adjustments to the disputed cost figures laid out in the 2019 audit. This position comes in direct response to ExxonMobil’s argument that the full $214 million should not be classified as cost oil.
For context, total exploration spending across the Stabroek Block between 1999 and 2017 added up to $1.6 billion. If ExxonMobil concedes that the $214 million cannot be counted as cost oil, Guyana will be entitled to half of that sum – equal to $107 million – with the remaining portion distributed to the Stabroek Block co-venturers: ExxonMobil itself, US energy firm Hess, and China National Overseas Oil Company (CNOOC).