In a lawsuit, Lululemon accuses Costco of selling knockoffs of the athleisure brand

Luxury athletic brand Lululemon is suing Costco, accusing the wholesale club giant of copying several of its signature designs and offering them at a lower price under its Kirkland Signature brand.

In a lawsuit filed Friday, Lululemon said that “given the success” of its products, “some companies have replicated or copied Plaintiffs’ proprietary apparel designs to create what are colloquially known in the fashion world as ‘knockoffs’ or ‘dupes.’ ”

“The Infringing Products create an improper association with Plaintiffs’ authentic products,” the complaint continued, citing the example of the hashtag “LululemonDupes” on social media, which helps users find reviews and sources of similar products at a lower price.

The lawsuit also accuses Costco of illegally trading on Lululemon’s “reputation, goodwill and sweat equity by selling unauthorized and unlicensed apparel” based on the athleisure brand’s design patents.

In a statement to NPR, Lululemon said: “As an innovation-led company that invests significantly in the research, development, and design of our products, we take the responsibility of protecting and enforcing our intellectual property rights very seriously and pursue the appropriate legal action when necessary.”

Costco did not immediately respond to a request for comment.

Lululemon was founded in Vancouver, British Columbia, in 1998 and has emerged as a leading retailer in the fashionable athletic space. With single items regularly ringing in at more than $100, the brand is heavily associated with the athleisure style of workout gear. Its revenues topped $10 billion last year.

Costco, which is membership only, has developed a devoted following for its private label Kirkland Signature brand, which makes competing products of name-brand products, usually at a far lower price to customers. Costco’s revenue totaled $254.5 billion in fiscal 2024.