In-N-Out Burger is taking Smashburger to court, after claiming the “Smashburger Triple Double” too closely resembles their famous “Double-Double” burger.

In their trademark infringement lawsuit filed Monday, In-N-Out claimed that Smashburger’s newest item will “likely confuse and mislead the consuming public,” into believing the two fast food chains and their products are affiliated, The Orange County Register reported.

The California-based company claimed they’ve had trademarks for its Double-Double since 1948 and Triple Triple since 1966. The “Smashburger Triple Double,” which includes three cheese slices and two patties, was unveiled in July.

In comparison, In-N-Out’s Double-Double combines two beef patties and two slices of American cheese while their “Triple Triple” (often referred to as 3×3) is made with three patties and three slices of American cheese, Eater pointed out.

Founded in 2007, Smashburger boasts their use of gourmet toppings, including sauteéd crimini mushrooms, goat cheese, and applewood-smoked bacon. Like their competitor, Colorado-based Smashburger uses buttered sponge-dough buns, according to The Register.

Despite holding two trademarks, TMZ reported that In-N-Out admitted that they don’t hold a trademark for the name “Triple Double.” However, they argued that In-N-Out customers frequently customize their order with similar items.

[Featured Image: Instagram/In-N-Out/Smashburger]