Skechers USA Inc. said it has filed suit against Sears Holdings Corp., accusing it of selling knock-off footwear that infringes on patents and trademarks for its Shape-up toning shoes and other lines.

A few hours before the Tuesday markets closed, the Manhattan Beach manufacturer and retailer accused Sears of selling the offending shoes at Sears and KMart stores, and on websites such as TheraShoe and Melrose Avenue.

“Skechers has invested tremendous resources into designing, developing and marketing our Skechers Shape-ups, Twinkle Toes and Z-Strap product lines,” said Philip Paccione, Skechers general counsel, said in a statement. “While we value our relationship with Sears, their actions are causing us tremendous damage, and we simply cannot let any company, let alone a company the size of Sears, infringe on our most valuable intellectual property.”

The suit, filed in the U.S. District Court for the Central District of California in Los Angeles, seeks damages as well as relief for the alleged infringements and unfair competition. Sears Holdings is based in suburban Chicago.

Shares closed up 33 cents, or 1.7 percent, to $20.05 on the Nasdaq.