Jimmy Buffett is a stickler for punctuation. The singer, who signs of a laid-back, island lifestyle in songs like “Cheeseburger in Paradise” and “Fins,” seems to have a pretty good grasp on his business empire. And when he spotted an application by footwear chain The Walking Company to trademark the phrase “It’s Five O’Clock Somewhere!” he had to step in.

“It’s Five O’Clock Somewhere,” sans exclamation point, was trademarked years ago, Buffett’s Margaritaville Enterprises LLC said in a complaint with the Trademark Trial and Appeal Board. He also reminded the board members that the duet with “renowned recording artist Alan Jackson” was the number one country song of 2003 and still ranks in the top 40 Billboard “Hot Ringtones.”