Here is a report detailing the various attacks the IPCC has been subjected to over the years. Including tracking down their originators. It was compiled by Greenpeace USA, and I believe it worth sharing:
Dealing in Doubt
The Climate Denial Machine vs. Climate Science
On this page
A brief history of attacks on climate science, climate scientists and the IPCC.
September, 2013.
DEALING IN DOUBT: FULL REPORT
"Doubt is our product, since it is the best means of competing with the 'body of fact' [linking smoking with disease] that exists in the mind of the general public. It is also the means of establishing a controversy...”
Tobacco company Brown and Williamson internal document, 1969
“Skepticism is not believing what someone tells you, investigating all the information before coming to a conclusion. Skepticism is a good thing. Global warming skepticism is not that. It’s the complete opposite of that. It’s coming to a preconceived conclusion and cherry-picking the information that backs up your opinion. Global warming skepticism isn’t skepticism at all.”
John Cook of Skepticalscience.com