It was the poster that helped inspire a nation and brought about "change." Now artist and Obey architect Shepard Fairey is admitting that his famous Barack Obama "HOPE" poster was indeed based on an Associated Press photo.

According to the Associated Press, Fairey admitted concealing a key mistake in his lawsuit over the poster, but said that the error should not be viewed as ''premeditated and sinister.''

The Los Angeles native, who was at Pittsburgh's Warhol Museum for the opening of his latest exhibition, admitted that he didn't use The Associated Press' photo of Obama seated next to actor George Clooney he originally said his work was based on and which he claimed would have been covered under ''fair use,'' the legal claim that copyrighted work can be used without having to pay for it. Instead he used a picture the AP has claimed was his source. Fairey said that he tried to cover up his error by submitting false images and deleting others.

The concession has caused the noted artist his fair share of trouble. On Friday (Oct. 16), Fairey's attorneys said they are withdrawing from his case -- in February, he sued the AP arguing that he didn't violate copyright law -- and that the artist had misled them as well. Despite this, Fairey appears to be moving forward wiyh his lawsuit against the news outlet. According to reports, the AP will continue to pursue its countersuit as well.