The petition first emerged in April 1998 and was organized by Art Robinson of the self-proclaimed "Oregon Institute of Science and Medicine" (OISM) [their headquarters are the Photo Inset].
Along with the Exxon-backed George C. Marshall Institute, Robinson's group co-published the infamous "Oregon Petition" claiming to have collected 17,000 signatories to a document arguing against the realities of global warming.
The petition and the documents included were all made to look like official papers from the prestigious National Academy of Science. They weren't, and this attempt to mislead has been well-documented.
Along with the petition there was a cover letter from Dr. Fred Seitz (who has since died), a notorious climate change denier (and big tobacco scientist) who over 30 years ago was the president of the National Academy of Science.
Also attached to the petition was an apparent "research paper" titled Environmental Effects of Increased Atmospheric Carbon Dioxide. The paper was made to mimic what a research paper would look like in the National Academy's prestigious Proceedings of the National Academy journal. The authors of the paper were Robinson, Sallie Baliunas, Willie Soon (both oil-backed scientists) and Robinson's son Zachary. With the signature of a former NAS president and a research paper that appeared to be published in one of the most prestigious science journals in the world, many scientists were duped into signing a petition based on a false impression.