<blockquote>His work, which is focused on the United States, shows how a network of 91 think tanks and industry groups are primarily responsible for conservative opposition to climate policy. Almost 80 percent of these groups are registered as charitable organizations for tax purposes and collectively received more than seven billion dollars between 2003 and 2010.

Among those named as key nodes of the network were the <a href="http://www.aei.org/">American Enterprise Institute</a>, which claims to have no institutional position on climate change, and the <a href="http://www.heritage.org/">Heritage Foundation</a>, which campaigns on a number of issues.

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via <a href="http://arstechnica.com/science/2013/12/billion-dollar-climate-denial-network-exposed/">Billion-dollar climate denial network exposed | Ars Technica</a>.