Since 1998 plaintiff Heller has been selling in the US a chair designed by Mario Bellini. The chair has received various design awards and is in the collection of the Metropolitan Museum of Art in NY. Heller filed for and received trademark registration 3,270,850 for the shape of the Bellini chair:

Design Within Reach is a retailer of designer furniture. Since 1999 it has sold the Bellini chair and in fact spotlights Mario Bellini on its site (see above).
Heller now alleges that DNR has begun selling or will shortly begin selling a Bellini knock-off chair (the complaint is not yet on Pacer so I don’t have photos yet of defendant’s chair).
Previous chair disputes here and here.
Complaint Bellini Chair