The ads promoting Jack in the Box's new line of sirloin burgers take aim at Angus beef, which CKE, McDonald's
No one from Jack in the Box was immediately available to comment.
The suit was filed in federal court in Santa Ana, California.
CKE argues in the suit that the commercials falsely imply that Angus beef burgers come "from the rear-end and/or anus of beef cattle by creating phonetic and aural confusion between the words 'Angus' and 'anus."'
In one of the ads at issue, Jack in the Box's bubble-headed mascot, Jack, points to a diagram of meat cuts showing that sirloin comes from a cow's mid-section. A colleague asks Jack to point to the "Angus area" of the cow, and draws a circle in the air. Jack responds: "I'd rather not."
In another spot, a group of fictional Jack in the Box employees laugh uncontrollably when a co-worker says the word "Angus" during a presentation about its competitor's burgers.
The suit also says the ads mislead consumers by making an "apples to oranges" comparison between sirloin, which is a cut of beef, and Angus, which is a breed of cattle.
The suit seeks an order both to stop Jack in the Box from running the ads and for the company to run "corrective advertising." It also seeks unspecified damages.
CKE's higher-end burgers, such as the Six Dollar Burger line at Carl's Jr. and the Thickburger line at Hardee's, are made with Angus beef.
No. 1 restaurant chain McDonald's last year started testing a line of Angus beef burgers in Southern California, where both CKE and Jack in the Box are based.
Burger King also sells some burgers made with Angus beef.