Costco Was Once Sued For $200,000 Over Worms In Its Frozen Halibut

Costco is known for many positive aspects, from its free sample policies to its delicious and inexpensive food court — not to mention Costco's beloved bakery offerings. But even this wholesome wholesaler has been in hot water before. In 2022, a California doctor and his family sued Costco over contaminated seafood, asserting that the Kirkland frozen Wild Pacific Halibut Fillet they purchased from their local store was infested with live worms. The family purchased the infested meat from a store in San Dimas.

As alleged in the lawsuit, the family cooked the fish the same day they purchased it and served it to their two children. As the couple's 13-year-old daughter picked through the meat, the live worms emerged. The couple had already eaten some of the product.

The lawsuit levied against Costco Wholesale Corp. alleges breach of warranty, failure to warn, negligence, product liability, and violation of the Unfair Competition Law of California. The plaintiffs of the case sought $200,000 in damages.

Gross but true: Worms in fish are not uncommon

While finding a worm in any food product might be cause for disgust, the truth is that these incidents are not uncommon — especially when it comes to halibut specifically. The worms typically found in halibut, called nematodes or parasitic roundworms, occur in roughly 20% of fish at processing plants or fishmonger counters. They're so common that most processors just cut out the worms while preparing the fish rather than throwing out the filet altogether.

While the CDC notes eating these worms can cause an illness called anisakiasis when the fish has been undercooked or served raw, when cooked properly they shouldn't make you sick. Dead nematodes are present in plenty of cooked fish including salmon and tuna; though with fish like tuna that are typically prepared rare, it's important to properly prepare the seafood by freezing it first. This also kills the nematodes and renders them edible — unappetizing, certainly, but edible.

Costco's fishy legal trouble

This incident isn't the only time a major market chain has been sued, Aldi's was sued as well. And, the most recent time Costco has been taken to court over its seafood was in 2023, when the warehouse was targeted by a class-action lawsuit challenging its assertions about its Kirkland-brand canned tuna.

The lawsuit states that Kirkland Signature White Albacore Tuna in Water is advertised as "dolphin safe," but that the fishing methods used to gather the tuna for the product harms and injures dolphins and other marine life. The plaintiff cites Costco's 2002 deal with Bumble Bee tuna as evidence: Bumble Bee is known for using a practice called "longline fishing" which can result in catching not just tuna but other species such as dolphins as well.

Though Costco sought a dismissal for this lawsuit, as of now the case is still ongoing. If it continues through court or reaches a settlement, affected Costco shoppers may be entitled to compensation. As for the worms-in-halibut lawsuit, Costco reportedly settled out of court.