The artist behind the comic Questionable Content has fallen in the crosshairs—or should we say "the horsehairs"— of retail behemoth Walmart. The mega-retailer is demanding that Jeph Jacques "discontinue any and all use" of the walmart.horse domain, which renders at a tumblr and displays a horse in front of a Walmart store.

Here's a snippet from Walmart's cease-and-desist letter Sunday:

Your use of a Domain Name that incorporates the famous Walmart mark constitutes trademark infringement and dilution of Walmart's trademark rights and unfair competition. Your use of our mark in the Domain Name is diluting use because it weakens the ability of the Walmart mark and domain name to identify a single source, namely Walmart. Further, your registration and use of the Domain Name misleads consumers into believing that some association exists between Walmart and you, which tarnishes the goodwill and reputation of Walmarts products, services, and trademarks.

The 34-year-old Massachusetts cartoonist said in an e-mail to Ars that the site is satire at its finest.

The idea behind the site started out as a conversation with a friend of mine—we were extremely amused by the new .horse TLD and decided to register a bunch of ridiculous domain names with it. As for its meaning, it’s a piece of postmodern Dadaism—nonsense-art using found objects, in this case publicly available images and the name of an megacorporation. Its purpose is to provoke exactly the kind of response it has received, and in doing so to parody the Walmart corporation and its actions. Claiming that walmart.horse defames the Walmart brand somehow is the highest possible satire, and the fact that this accusation came from Walmart itself is a most delicious piece of irony.

Walmart isn't laughing, however, and is demanding that Jacques stop using the domain within two weeks. Jacques responded to Walmart, saying that the domain is "an obvious parody and therefore falls under fair use. Publicly available images of a horse, a Walmart store, and comical music make it clear that the site is meant to be a joke. I would be happy to provide a disclaimer on the website explicitly stating this. If you have any requests for other animals you would like to see added to the image on the website, I would happily comply!"

So, what does the law say about this? A fair use defense is available to both copyright and trademark infringement claims, and they're decided on a case-by-case basis.

The Supreme Court ruled in 2004 that the party asserting a trademark fair use defense "need not entirely negate the likelihood that the consumers will be confused about the origin of the goods or services affected." (PDF) That said, when it comes to Internet domains, the Internet Corporation for Assigned Names and Numbers (ICANN) routinely sides with trademark holders challenging a domain registration.

Walmart did not immediately respond to a request for comment.