ExxonMobil and the Climate Change Controversy: A Betrayal of Public Trust
Updated: Oct 8
Few corporate stories have shaped the climate debate as much as ExxonMobil's. Investigative reporting in 2015 alleged that the company understood the science of climate change decades ago while publicly casting doubt on it. ExxonMobil has always rejected that account. A decade on, the story is still being argued in court, and it has changed how regulators and standard-setters think about climate disclosure.
Updated October 2026: this post has been revised to reflect the court outcomes to date, including the 2019 New York ruling and the Massachusetts case, and now explains what the controversy means for climate-related disclosures in IFRS financial statements.
History of ExxonMobil
ExxonMobil, born from the union of Exxon and Mobil, giants of the petroleum industry, has been a crucial player in the energy sector since its inception in 1999. However, its roots go deeper, tracing back to John D. Rockefeller's Standard Oil Company. While ExxonMobil is known worldwide as an energy provider, it is its record on climate change that has drawn the most attention in recent years. This article looks at that record, the allegations made against the company, and what the courts have decided so far.
ExxonMobil's record has drawn allegations of climate change denial. Critics point to its past funding of organisations that questioned mainstream climate science, which sits uneasily with its public commitments to reduce emissions. That tension is the heart of the controversy.
Initial Climate Change Findings
The ExxonMobil climate change saga begins in the late 1970s:
Late 1970s: Exxon scientists began researching how carbon dioxide from burning fossil fuels affects the climate.
Early 1980s: Internal projections modelled the warming that rising CO2 concentrations would cause. A 2023 study in Science by Supran, Rahmstorf and Oreskes found these projections were broadly accurate.
Late 1980s onwards: Exxon, and later ExxonMobil, became a prominent public voice questioning the certainty of climate science, including through industry groups such as the Global Climate Coalition.
Critics argue that the gap between this internal research and the company's public messaging amounted to deception. ExxonMobil says its scientists' work was published in peer-reviewed literature and that its public statements reflected genuine scientific uncertainty at the time.
The Allegations
Corporate Strategy
Critics allege that ExxonMobil's strategy was to protect its core business by emphasising uncertainty in climate science, even as its own scientists' work pointed the other way.
Misinformation Campaigns
The company, and industry groups it supported, funded advertising and think tanks that questioned the scientific consensus. Critics describe this as a misinformation campaign; ExxonMobil has rejected that description.
Lobbying Efforts
Critics also point to lobbying, directly and through trade associations, against climate measures such as the Kyoto Protocol.
Investigation & Court Proceedings
In 2015, InsideClimate News and the Los Angeles Times, the latter working with Columbia University's journalism school, published investigations into what Exxon had known about climate change and when. The reporting prompted investigations by state attorneys general and the US Securities and Exchange Commission (SEC), and a wave of lawsuits by states, cities and investors.
The outcomes so far have been mixed. The SEC closed its investigation in 2018 without bringing an action. New York's Attorney General sued in 2018, alleging that ExxonMobil misled investors about how it accounted for the cost of future climate regulation; after a trial, the New York Supreme Court ruled for ExxonMobil in December 2019. Massachusetts' Attorney General brought a separate case in 2019 under the state's consumer protection law. ExxonMobil's attempts to have it dismissed failed, and the case was still in pre-trial proceedings in 2026.
Media Coverage & Public Response
The media played a pivotal role in this saga:
Investigative Media: InsideClimate News and the Los Angeles Times led the journalistic effort to expose ExxonMobil's deception.
Public Outcry: The revelations sparked widespread public outrage and led to a renewed focus on corporate responsibility.
Media Condemnation: The media heavily criticized ExxonMobil's actions, calling for greater transparency and accountability.
The public response was overwhelming. People from across the globe denounced ExxonMobil's actions and called for stringent measures to combat climate change.
ExxonMobil's Defence and the New York Ruling
ExxonMobil has consistently denied wrongdoing. It argues that its climate research was published openly and that it has acknowledged the risks of climate change for many years.
There was no settlement in New York. The case went to trial in October 2019, and the court found that the Attorney General had not proved that any misstatement was material to investors. The judge was explicit, though, that the ruling was about securities fraud, not about ExxonMobil's responsibility for contributing to climate change. Critics continue to argue that the company's changes have been too little, too late.
Why the Controversy Still Matters
Whatever the courts finally decide, the controversy reaches far beyond the company. Critics argue that decades of public doubt about climate science slowed action on emissions, and the case has become a reference point in every debate about corporate accountability for climate change.
It has also sharpened demands for transparency. Investors now expect companies to explain how climate risk affects both their strategy and their numbers, and regulators and standard-setters have responded.
The ExxonMobil story is a reminder that the fight against climate change is also a fight for reliable information. In that fight, truth and transparency must prevail.
What the Case Means for Financial Statements Today
The New York case turned on an accounting question: how ExxonMobil applied proxy costs of carbon in its investment decisions, impairment assessments and reserves estimates. That question has since moved to the centre of financial reporting.
IFRS Accounting Standards have no climate standard, but climate-related risks already flow through existing requirements. In November 2025 the IASB published illustrative examples, Disclosures about Uncertainties in the Financial Statements, which use climate-related uncertainties to show how those requirements apply. They are accompanying guidance with no effective date, so entities are expected to consider them promptly. The main pressure points are:
Materiality: information about climate-related matters can be material even when the amounts are not, if users would expect it given the entity's public statements and transition plans.
Impairment (IAS 36): cash flow projections should rest on reasonable and supportable assumptions, including carbon prices and any transition plans the entity has announced.
Useful lives and decommissioning (IAS 16 and IAS 37): assets that may be retired early, and obligations that may fall due sooner, need their estimates revisited.
Judgements and estimation uncertainty: where climate assumptions could cause a material adjustment, the significant judgements, key sources of estimation uncertainty and sensitivities should be disclosed (IAS 1, carried into IAS 8 when IFRS 18 takes effect in 2027).
Alongside the financial statements, IFRS S2 asks for climate-related disclosures, including how climate risks affect the entity's financial position and performance. The lesson from ExxonMobil is connectivity: what a company says publicly about climate should match the assumptions in its accounts.
The ExxonMobil controversy is a lesson for all of us. It shows how much depends on a company telling the same story inside and outside its annual report. As investors, consumers and citizens, we must keep demanding transparency and accountability. In the face of climate change, we cannot afford anything less.
