From their website:

What's all this about

Since 1998, the year after the Kyoto Protocol was founded, we have been following the money donated to the groups campaigning against the science of – and action on – global warming. The think tanks are largely American-based, although there are some based in the UK and Canada which Exxon funds. These funding figures have been published by ExxonMobil in annual reports on its website and collected, over the years, by Greenpeace and allies.

We have also sourced information from the Internal Revenue Service’s 990 forms, submitted by law by ExxonMobil. However, we know we do not have the full picture. Aside from missing data for 1999 when Exxon didn’t publish these grants, we don’t have the funding figures of groups ExxonMobil funds through other channels internationally. And we know of several grants and ‘projects’ Exxon has launched on this front that were not included in their public reports.

We have divided this section into three distinct groups: the organizations funded by ExxonMobil, the people who work for and with them, and the scientists they use to dispute the science.