08/23/2012 05:43 pm ET

Lululemon Sues Calvin Klein Over Patent Infringement

We tend to glaze over when reading legal jargon, but today's news brings a legal debate that's piqued our interest.

Lululemon, purveyor of expensive yoga pants for taut mommies everywhere, is suing Calvin Klein over their "Astro" pants. But the lawsuit doesn't center on a stolen logo or brand name, as many fashion-on-fashion suits do; instead, Lululemon is accusing Calvin Klein of patent infringement. Lululemon claims Calvin Klein ripped off (so to speak) the "Astro" waistband as well as two other design elements.

Patents are a rare thing in fashion, Fashionista notes, as most patents are utility patents, referring to the function of an invention. Yet design patents refer to the "ornamental aspects of an invention," a distinction that can be hard to pin down. As Susan Scafidi, academic director of the Fashion Law Institute at Fordham University Law School, told the Vancouver Sun:

"Take the average polo shirt, for example. The design isn’t new, so it can’t be patented — novelty being the most basic requirement of patentability — but it’s easy to stitch a logo over the heart and gain instant legal protection, at least for that little crocodile, polo pony, or other trademark."

Thus we see trademark lawsuits all the time (for example, Gucci's court battle against Guess). Design patent court battles? Not so much.

Design patents are hard to obtain in the first place, notes lawyer Adrian Pruetz. "It's very hard to come up with something that's new and that hasn't just been part of the clothing vernacular," Pruetz told the Chicago Tribune, and then it can be hard to protect those designs. But pursuing design patents can be worth it, Scafidi pointed out to Fashionista, if the design element will be used again and again in multiple collections.

Lululemon filed its suit against Calvin Klein and their manufacturer, G-III Apparel, last week in Delaware. Stay tuned to see the outcome... fingers crossed for a highly entertaining, multi-day court battle a la Gucci vs. Guess. That was so fun!

Read more in the Chicago Tribune.

See more designer skirmishes...

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