Conservative billionaires used a secretive funding route to channel nearly $120m (77m) to more than 100 groups casting doubt about the science behind climate change. The funds, doled out between 2002 and 2010, helped build a vast network of thinktanks and activist groups working to a single purpose: to redefine climate change from neutral scientific fact to a highly polarising wedge issue" for hardcore conservatives. The millions were routed through two trusts, Donors Trust and the Donors Capital Fund. Donors Capital caters to those making donations of $1m or more. By 2010, the dark money amounted to $118m distributed to 102 thinktanks or action groups which have a record of denying the existence of a human factor in climate change, or opposing environmental regulations. The money flowed to Washington thinktanks embedded in Republican party politics, obscure policy forums in Alaska and Tennessee, contrarian scientists at Harvard and lesser institutions. And it was all done with a guarantee of complete anonymity for the donors who wished to remain hidden. "The funding of the denial machine is becoming increasingly invisible to public scrutiny. It's also growing. Budgets for all these different groups are growing," said Kert Davies, research director of Greenpeace, which compiled the data on funding of the anti-climate groups using tax records. "These groups are increasingly getting money from sources that are anonymous or untraceable. There is no transparency, no accountability for the money. There is no way to tell who is funding them," Davies said.