For background, let’s go to Alexander Aciman’s exhaustive comparison of a pair of two pairs of pants: one sold by lululemon, and one sold under Coscto’s in-house brand Kirkland Signature. This was ...

Lululemon, the prestigious sportswear brand, has filed a lawsuit against Costco, accusing it of selling replicas of its products under the Kirkland brand.

Kirkland Signature is now bigger than some of the world’s biggest companies—and it has become essential to Costco’s business.

Lululemon is accusing Costco of leading customers into believing that the Kirkland-branded “dupes are in fact manufactured by the authentic supplier of the ‘original’ products.” ...

Lululemon is accusing Costco of leading customers into believing that the Kirkland-branded “dupes are in fact manufactured by the authentic supplier of the ‘original’ products.” ...

NEW YORK — Lululemon is suing Costco, alleging that the discount wholesaler is selling knockoffs of its $128 pants and other pricey athleisure clothing. In a lawsuit filed Friday, Lululemon said ...