After analysing 279 companies worldwide, from a range of sectors and countries, the researchers found that more than a quarter (75 of 279) were underreporting GHG by at least 20%.
Of those, firms within the energy sector were overrepresented: US based oil and gas companies made up 44% of the companies found to be underreporting, compared to 14% in the whole dataset.
The team also found that almost half (47%) of the underreporting companies they identified said that their social responsibility and sustainability reporting is audited.
“If a significant proportion of companies worldwide are materially underreporting their GHG emissions, then efforts to decarbonise the global economy may be further out of reach than previously thought,” said lead researcher, Marc Lepere, Professor of Practice in Sustainability at King’s Business School.
Financial regulators worldwide are taking steps towards making company reporting of GHG emissions mandatory. For instance, the European Union Carbon Border Adjustment Mechanism (effective January 2026), will require importers of carbon-intensive products to declare emissions embedded in the product’s supply chain and buy certificates to an equivalent value based on the EU carbon market price.
By establishing consistent and comparable emissions disclosures, regulators hope to incentivise decarbonisation efforts by encouraging firms to develop an accurate picture of their full carbon footprints and enabling financial markets to price this information.
However, the research team say this fresh evidence on the scale of inaccuracies in reported GHG emissions means that GHG reporting by companies, while necessary, is by itself unlikely to ever be a sufficient basis for policy.
“Our findings suggest that the GHG Protocol as currently devised is not sufficiently robust to underpin regulators’ goals,” added Marc Lepere. “Regardless of whether underreporting is deliberate or not, underreporting companies have a misleading understanding of their carbon footprints.
“And when one company underreports, this has a knock-on effect on the emissions reported by their customers, exposing them to reputational and financial risk too.”
Highlighting the apparent connection between a company’s industry and location and the likelihood that it was under-reporting its GHG emissions, the team said:
“We find that if you knew nothing about a company other than it was headquartered in the U.S. and it operated in the oil and gas sector, then you would increase the probability assigned to this company being in the underreporting category by 48% points.”
As a result of their findings, the researchers are recommending policymakers make it standard practice to use advanced measurement data from satellite and remote sensing technologies to automatically observe annual methane emissions from oil and gas facilities.
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Notes to editors:
For any press queries or to request interviews with the researchers, please contact joanna.dungate@kcl.ac.uk and catherine.sirikanda@kcl.ac.uk / business@kcl.ac.uk
The full report, Emissions dissonance: Examining how firm-level under-reporting undermines policy is available here: https://www.kcl.ac.uk/business/assets/PDF/research-papers/lepere-emissions-dissonance-sele2025.pdf