A couple of comments from the Pruitt Panda Bear appropriation = flash mob protest thread worth highlighting below. Thanks to Greg.org for contributing some additional thoughts.
Greg.org: First, while the unfamiliarity with the art world's history of appropriation is probably to be expected, it's interesting to see that for all the passionately fought arguments in that Emptees thread, there is absolutely no evidence of any actual knowledge of intellectual property law or standard practices.
Second, I think it's too annoying to be sustainable, but if appropriation [or appropriating without credit, I guess] is only morally acceptable when it happens upward [i.e., when Pruitt rips off Mickey Mouse and Coke, but not when he, a very successful fine artist, reworks an image from lowly t-shirt designers making "$7,500 in three months" from their art], then we should probably look more closely at who's being ripped off.
Threadless is independent, but it is the 800-lb gorilla of the t-shirt market. AJ and Jimiyo are two prominent designers in that large community. In his dayjob, AJ is actually an art director for OgilvyOne, and he took Jimiyo's design, flipped it, added some saliva, and submitted it. There was some mild grousing at the time about Threadless [or AJ?] not giving credit to his own source/colabo partner. Obviously, by this point, the Law of the T-shirt Jungle helped settle that issue.
SO it's arguable that Pruitt's use is not, in fact, anonymous theft, a quote of a design and from a source that are well-known in its milieu. He did a bunch of t-shirt paintings and actual t-shirts; do we know that t-shirt design was NOT a reason for Pruitt using that image?
And finally, the t-shirt mob's anger is fueled in part by their misunderstanding of Maccarone's statement about Rob's “trademark panda” or whatever. To anyone familiar with his work, that's obviously a reference to his decade-long use of panda imagery, NOT to any claim that the images in his work are his original property. That nuance is lost in this debate. I'd wager that every single panda Pruitt's ever painted has been cribbed from somewhere, and that this Universal Panda-ism is central to his interest. And it's also the cuddly context that makes the Threadless design work in the first place.
Paddy Johnson: Appropriation without credit tends to be a little more morally acceptable when it moves upward not just because of class norms, but for the recognizability of those images. Pruitt could name his painting Walt Disney/Deitch/Pruitt, but the necessity of calling attention to the source is lessened by the fact that it's already part of the cultural vocabulary. I would guess though, the impulse to title works in such a way that directly references more recognizable sources actually goes up with their own recognizability. People naturally identify with products all the time as a means of constructing identity, so naming the more recognizable ones would be a natural tendency.
As for the actual t-shirts and the t-shirt canvases, I think the t-shirt source would be a good reason not to put the iconography on his own. Given the aesthetics of Pruitt's own line of shirt though, I'm guessing the thought never crossed his mind, as the image would make no sense in the context of this series.