Athleisure brand Lululemon has filed a lawsuit against Costco, alleging that the warehouse club chain sold lower-priced duplicates of its products.

Lululemon claims Costco sold unauthorised and unlicensed apparel that uses knockoff, infringing versions of its patents, according to US ABC News.

The complaint highlights that Costco’s private label Kirkland Signature offers products that copy Lululemon’s popular designs, such as Scuba hoodies, Define jackets, and ABC pants.

It also alleges that the practice misled consumers into thinking that the authentic supplier manufactures Kirkland-branded versions of the original products, and that the discount retailer did not attempt to dispel the ambiguity.

“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,” a Lululemon spokesperson said in a statement.

The brand is seeking an unspecified amount in monetary damages and an order for Costco to stop selling the alleged duplicates.

In 2021, Lululemon sued Peloton over a line of workout clothes that copied its proprietary designs. The exercise bike maker later agreed to phase out certain products named in the lawsuit.

Last month, Lululemon announced it would cut approximately 150 corporate jobs as part of its organisational restructuring.