Download the Study

You can view the abstract summary and download the Carbon Majors study here: Tracing anthropogenic carbon dioxide and methane emissions to fossil fuel and cement producers, 1854-2010: Climatic Change, online 21 November 2013.

Download the Methods & Results Report here.


In groundbreaking peer-reviewed research forthcoming in Climatic Change, researcher Richard Heede offers the most complete picture to date of which institutions have extracted the fossil fuels that have been the root cause of global warming since the Industrial Revolution.

Rather than attribute emissions to nations, the study aggregates historical emissions according to carbon producing entities themselves. Heede concludes that nearly two-thirds of carbon dioxide emitted since the 1750s can be traced to the 90 largest fossil fuel and cement producers, most of which still operate. online

The research attributes 63 percent of the carbon dioxide and methane emitted between 1751 and 2010 to just 90 entities. Fifty are investor-owned companies such as Chevron, Peabody, Shell, and BHP Billiton. Thirty-one are state-owned companies such as Saudi Aramco and Statoil, and nine are government-run industries in countries such as China, Poland, and the former Soviet Union. The research also classified the 90 entities according to type of fossil fuel extracted and marketed.

There are 56 oil and natural gas companies, and 37 coal producers. In addition, the CO2 emissions from seven cement manufacturers are included.

Top 20 investor- and state-owned entities and attributed CO2 & CH4 emissions 2010

Entity 2010 EmissionsMtCO2e Cumulative 1854-2010MtCO2e Percent of Global1751-2010
1. Chevron, USA 423 51,096 3.52%
2. ExxonMobil, USA 655 46,672 3.22%
3. Saudi Aramco, Saudi Arabia 1,550 46,033 3.17%
4. BP, UK 554 35,837 2.47%
5. Gazprom, Russian Federation 1,371 32,136 2.22%
6. Royal Dutch/Shell, Netherlands 478 30,751 2.12%
7. National Iranian Oil Company 867 29,084 2.01%
8. Pemex, Mexico 602 20,025 1.38%
9. ConocoPhillips, USA 359 16,866 1.16%
10. Petroleos de Venezuela 485 16,157 1.11%
11. Coal India 830 15,493 1.07%
12. Peabody Energy, USA 519 12,432 0.86%
13. Total, France 398 11,911 0.82%
14. PetroChina, China 614 10,564 0.73%
15. Kuwait Petroleum Corp. 323 10,503 0.73%
16. Abu Dhabi NOC, UAE 387 9,672 0.67%
17. Sonatrach, Algeria 386 9,263 0.64%
18. Consol Energy, Inc., USA 160 9,096 0.63%
19. BHP-Billiton, Australia 320 7,606 0.52%
20. Anglo American, United Kingdom 242 7,242 0.50%
Top 20 IOCs & SOEs 11,523 428,439 29.54%
Top 40 IOCs & SOEs 546,767 37.70%
All 81 IOCs & SOEs 18,524 602,491 41.54%
Total 90 Carbon Majors 27,946 914,251 63.04%
Total Global Emissions 36,026 1,450,332 100.00%

The U.S. Department of Energy’s Carbon Dioxide Information and Analysis Center database pegs cumulative global emissions since 1751 at 1,323 gigatonnes of carbon dioxide (1,450 GtCO2e including methane).


Heede’s research reveals:

Emissions traced to investor-owned entities clock in at 315 gigatonnes of carbon dioxide equivalent, narrowly surpassing emissions from government-run industries, which totaled 312 gigatonnes. State-owned companies contributed 288 gigatonnes.

The largest investor-owned producers have had an outsize effect on emissions. The top 20 produced fuels that comprised 29.5 percent of emissions, while the top 10 account for 15.8 percent.

Half the emissions traced to the 90 “carbon majors” have occurred since 1986, demonstrating the increasing speed with which fossil fuels are being burned.


Heede spent eight years combing through publicly available records including annual reports in the collections of public and academic libraries, filings with the U.S. Securities and Exchange Commission, and other public sources. He collected data on crude oil, natural gas, coal, and cement production worldwide by three types of entities: investor-owned (e.g. ExxonMobil), state-owned (e.g. Saudi Aramco) and government-run entities (e.g. North Korea’s coal industry).

The availability of production data for each entity and the timing of Heede’s research dictated the dominant timeframe (1854-2010) for this study. The threshold for inclusion was at least 8 million tonnes of carbon (MtC) produced in a recent year, which focused attention on a manageable number of entities and highlighted those companies responsible for most of the current warming.

When an entity merged or was acquired, its emissions prior to that point were attributed to the extant entity. To accurately account for carbon dioxide emissions, all non-combustion uses of hydrocarbon, such as oil used for petrochemicals, lubricants, and asphalt were subtracted and the amount of CO2 each fuel type releases upon combustion calculated. To ensure conversion rates were standardized, the analysis relied on international guidelines for carbon content of all fuel types.

The analysis also included calculations of a producer’s direct emissions via flaring and venting processes, emissions from entities using their own fuel, and fugitive emissions of methane from oil and gas operations and coal mining.


It’s difficult for researchers to find complete extraction records, so there are advantages to greater corporate and government transparency requirements, including more thorough assessments of direct and product-related emissions.

In addition to further analysis that can be conducted through the dataset itself, the approach — looking at producers rather than nations — opens many doors for future research. Scientists running climate models, for instance, could use this data to determine how different effects of climate change can be attributed to the 90 entities in the study.

The results may also have practical policy applications. The United Nations Framework Convention on Climate Change, the primary forum for international climate discussions, typically focuses on responsibility at the country level. This research provides another lens to examine global climate policy because it offers the first comprehensive accounting of historical emissions from producers, including many multinational institutions that initially extracted fuels from the earth.