OK Go, the rock band best known for their viral and elaborate music videos, is making headlines these days for another reason. As reported by Variety, the band filed a trademark lawsuit against Post Foods, who recently released an “anytime, anywhere cereal bowl” called, how could it be otherwise, OK GO! News of the legal troubles began earlier this year when the band themselves posted about it on social media, accusing them of trademark infringement. Post has asked a judge for a “declaratory judgment” in their favor, but given the circumstances, it may not be that easy.

“We’ve been sued by Post Foods,” OK Go’s Instagram post reads, the band reads. “Has your name ever been stolen by a multi-billion dollar food processor Goliath? Here’s how it goes: 1) They file for a trademark on the name you’ve been using for 25 years. 2) You send them a letter asking for a choose another name, please. 3) They CHALLENGE YOU IN FEDERAL COURT. Plus, according to Post, this breakfast is “ready to rock.”

At the heart of trademark cases is the “likelihood of confusion” it would create for the public. According to the US Patent and Trademark Office, the “likelihood of confusion” can be due to factors such as: “When brands sound similar when spoken, are visually similar, and/or convey the same overall commercial impression to the consumer public.” That certainly makes this an open and closed case for OK Go the band, but there’s also the factor that between these two trademarks they don’t really sell the same stuff.

As the USPTO states, even when marks prove confusing due to the nature of similarities, the “likelihood of confusion” only exists if the goods and/or services of the two trademarks are “related”. There is some wiggle room as there is no requirement that they be identical goods/services, it is often enough that “consumers are likely to (erroneously) assume they come from a common source.” Something that seems plausible in this case.

“It’s furious… It’s like such cutting bullying,” OK Go singer Damian Kulash told Variety about the lawsuit. “There are so many other things you could call your damn cereal. Just pick one. Nobody looks good. Just choose a new name.’

“Our general policy is not to comment on pending litigation,” Post said in a statement. “However, we want to clarify that Post is not trying to stop the band OK Go from using its name in any way. Instead, we are simply asking a court to determine that Post is legally able to use the words OK GO! its new breakfast cereal product. The trademark law allows companies to use the same words for different types of goods and services, just as the word DELTA is used for cranes, air travel and dental insurance.’

To make things even more confusing, Post claims an attempt has been made to partner with their OK GO! cereal with OK Go the band, but the group refused. OK Go’s attorney disputed that, noting that “no offer was made.”