This is also one of the most problematic things about it, when it comes to intellectual property law (And here's a discussion of some of the reasons why it's so problematic from the last time a friend had work infringed upon via the Internet). Today, yet again, a friend of mine had copyrighted work infringed upon via the Internet, and in this instance, not only was there infringement, but it was infringement for profit, and without acknowledgement. That's pretty much like stabbing a creator in the heart and then twisting the knife.
Here, I'm talking about the amazingly talented comic book and pulp artist Francesco Francavilla, who called out Teefury.com today for infringing on a work he created in 2006. The image is of H.P. Lovecraft and Lovecraft's creation Cthulu, and was based on an old photo of Lovecraft. Francavilla sells the image on t-shirts and other items himself.
Teefury.com's image strongly resembles Francavilla's original art, in ways that go beyond a possible shared photo reference, and that would hinder an argument that Teefury's work was sufficiently transformative (i.e. created a new work) and thus defensible under fair use (which is, as I constantly remind people when I post about copyright, only a defense, not a right). As the linked ComicsAlliance article states, and as I can also see plainly, there are several points of commonality that I believe would lead to a finding for Francavilla if such a case were to go to court; the most telling being the distinctive design of the left (or Lovecraft's right) eye, which Francavilla originated. It's clear that the Teefury "artist" MUST have seen Francavilla's work, since such a detail is extremely original and not the sort of design element anyone drawing Lovecraft would immediately include.
But the problem here is not just the infringement; it is also in the nature of the way the Internet functions, and the way the Teefury.com website is set up, which could appear to limit the benefit for an artist of pursuing the infringement by the most common method of recourse, a cease & desist letter. Because Teefury.com only sells each tee-shirt for one day, by the time a traditional cease & desist-type letter demanding the art be removed was to be sent out and responded to (assuming a response), the tee-shirt would already have been taken down anyway as part of the course of ordinary business at Teefury; thus allowing the infringer to "get away with" the infringement for a day, while depriving the original artist of at the very least the satisfaction of knowing that they had successfully caused the infringing work to be removed by the infringer. It's a frustrating position for an artist to be in, to say the least; and it makes it easier for the website to get away with being a repeat offender, since an artist doing a cost/benefit analysis might assume the cost of taking action would outweigh the minor benefit of removal a few hours early, if at all.
What makes it more frustrating is the attitude of the infringer in this case (who, incidentally, makes a bald-faced claim to being the "artist" of the Lovecraft piece). This guy, who is actually one of the employees of Teefury (the "art director," as opposed to being a member of the public who submitted a work) has clearly expressed his blatant misunderstanding of U.S. copyright law and his disregard for the rights of artists, in a post entitled "STFU Comparison Police! Advice to Artists. His idiocy about the way copyright and fair use works would be laughable if it wasn't actually causing harm to artists.
But cause harm it does; not only in the infringement itself, but in the possible lost profits, and in the propagation of an attitude of irreverence towards copyrights and ownership amongst internet know-it-alls who think they're in the right when they are not, and encourage others to follow their lead.* (Though I'd love to see their reactions were someone to treat their works the same way and profit from them; I daresay there'd be some general about-facing and a quick hue and cry would be raised if the tables were turned).
That's why I would encourage artists to follow up on infringement anytime they possibly can; and, more importantly in cases such as this, to keep in mind that asking for an infringing work to be removed is not the only recourse an artist might have; in the instances where an infringer is making a profit, always remember that a copyright owner can demand an accounting of any profits, and a remittance of any profits derived from the work.
I also encourage people like the infringer over at Teefury to read up on U.S. copyright law, in hopes that they will realize they are, in fact, breaking the law, and it might just come back to haunt them.
*ETA: And, as J. Robert Deans of Twitter points out, there is also the harm of a day of lost work and income due to this issue distracting the artist from his current project.