Everyone’s favorite yoga clothing line, Lululemon, is suing Calvin Klein for violating several of its patents relating to its yoga pants. Yes. Patents. On yoga pants. Not exactly sure how that happened.

In any event, despite Lululemon’s explosive growth and dominance of the yoga clothing market (evidenced by the fact that you can hardly walk down the street, much less go to a yoga class, without seeing Lululemon logos everywhere), the company has been feeling the heat of increasing competition this year. And apparently, the company isn’t planning on taking things lying in shavasana.

The patents in question relate to Lululemon’s Astro Pant, pictured below. Follow the link to see a photo of the Calvin Klein pants at issue in the suit.

Lululemon sues Calvin Klein over pant patents.