Vegan Customer Sues Burger King for ‘Contaminated’ Impossible Whopper Allegedly Cooked on Same Grills as Meat

A Burger King customer who is vegan has sued the company for selling him an Impossible Whopper that was “contaminated” by meat by-products, according to claims in a new class action lawsuit.

Plaintiff Phillip Williams says he bought an Impossible Whopper at a Burger King in Atlanta, Ga., believing it to be completely meat-free. Williams, who adheres to a strict vegan diet, ordered the Impossible Whopper — without mayonnaise, which is not vegan — from Burger King’s drive-through in August 2019. While the burger arrived without mayonnaise as requested, Williams says he discovered after eating it that the patty was covered in meat by-products. He accuses Burger King of cooking the meat-free patties on the same grill where beef patties are made and of misleading customers by marketing the Impossible Whopper as a meat-free menu item.

“Despite Burger King’s representations that the Impossible Whopper uses the trademarked ‘Impossible Meat’ that is well-known as a meat-free and vegan meat alternative, Burger King cooks these vegan patties on the same grills as its traditional meat products, thus covering the outside of the Impossible Whopper’s meat-free patties with meat by-product,” the lawsuit says. The suit against the Miami-based fast-food chain was filed in the Southern District of Florida.

The Impossible Whopper, which became available throughout the U.S. in 2019, is a version of Burger King’s Whopper burger made out of plant-based “meat” produced by the Silicon Valley company Impossible Foods.

Williams says he was not told, nor did he see any signs, that the Impossible Whopper was cooked on the same grill as Burger King’s beef patties or other meat products. It is unclear how he discovered the alleged meat by-product on his burger.

The lawsuit seeks an injunction that requires Burger King to disclose that it cooks the Impossible Whopper on the same grill as its traditional meat items, compensatory damages for Williams and a jury trial. An attorney for Williams did not immediately respond to TIME’s request for comment.

Burger King describes the Impossible Whopper as, “100% Whopper, 0%” beef on its website. The company also notes that customers looking for a meat-free option can request a “non-broiler method of preparation.” Chris Finazzo, Burger King’s president in the Americas region, told Bloomberg in August that Burger King’s Impossible Whopper would be cooked in the same broiler where regular meat products are also prepared, unless a customer requested it be made separately.

A Burger King spokesperson said the company does not comment on pending litigation in a statement to TIME.