Lululemon on Monday followed through on its threat to sue Peloton over the “copycat products” in the exercise bike company’s new clothing line.

The Canadian athletic apparel maker sued Peloton in Los Angeles federal court, seeking triple damages for its rival’s alleged “willful” infringement of six design patents.

A pedestrian wearing a protective mask walks past a Lululemon store in San Francisco, California, U.S., on Monday, March 29, 2021. Lululemon Athletica Inc. is expected to release earnings figures on March 30. Photographer: David Paul Morris/Bloomberg via Getty Images

Lululemon filed its lawsuit five days after Peloton brought its own case in Manhattan federal court, seeking a declaration that Lululemon’s claims had no merit.

Peloton and its lawyer did not immediately respond to requests for comment.

The dispute arose from Peloton’s launch in September of a private-label apparel brand, following the end of the companies’ five-year co-branding relationship.

Lululemon said five Peloton women’s bra and legging products – Strappy Bra, High Neck Bra, Cadent Peak Bra, Cadent Laser Dot Bra and Cadent Laser Dot Leggings – infringed its patents.

It also said another Peloton product, One Lux Tight, is a knockoff of its Align pants, one of its all-time best sellers.

Peloton “intended to closely copy Lululemon’s proprietary designs and pass off its goods as Lululemon’s high quality products to misappropriate the immense goodwill that Lululemon has spent enormous time, effort, and expense to cultivate,” Lululemon said in its complaint.

The Vancouver, British Columbia-based company had in a Nov. 11 letter to Peloton threatened to sue unless sales of the alleged knockoffs were halted.

Peloton maintained in its lawsuit that customers would not have trouble telling the companies’ products apart, and Lululemon’s designs were not special enough to merit patent protection.

New York-based Peloton has sought to diversify its revenue streams, after sales growth for its bikes and treadmills slowed as more people received COVID-19 vaccines and stayed home less often.

The cases are Lululemon Athletica Canada Inc v Peloton Interactive Inc, U.S. District Court, Central District of California, No. 21-09252; and Peloton Interactive Inc v Lululemon Athletica Canada Inc, U.S. District Court, Southern District of New York, No. 21-10071.