Dupe or Infringement? Lululemon Files Lawsuit Against Costco
Published: July 6th, 2025.
Lululemon has filed a lawsuit against Costco, alleging that the retailer sells lookalikes of their high-end athletic apparel that could mislead consumers. The suit, filed in the U.S. District Court for the Central District of California, accuses Costco of infringing on trade dress and trademark laws by offering cheaper items that closely resemble Lululemon’s best-selling products.
The products in question include Lululemon’s Define jacket, Scuba hoodie, and ABC pants, which typically retail for around $128 each. Lululemon claims that Costco sells significantly cheaper alternatives under brand names like Danskin, Jockey, Hi-Tec, Spyder, and sometimes their own Kirkland label. In their filing, the company points to items such as the Hi-Tec Men’s Scuba Full Zip, priced at just $19.97, as examples of confusingly similar products.
Lululemon argues that “some customers incorrectly believe these infringing products are authentic Lululemon apparel.” The lawsuit also states, “Indeed, one of the purposes of selling 'dupes' is to confuse consumers at the point-of-sale and/or observers post-sale into believing that the 'dupes' are Plaintiffs' authentic products when they are not.”
Costco has not yet responded to the complaint or issued a public comment.
The rise of fashion dupes has created tension in the apparel industry. Shoppers are increasingly drawn to lower-cost alternatives that offer a look and feel similar to premium brands. Social media platforms, especially TikTok, have helped normalize this trend through viral hashtags like #lululemondupes, where users showcase side-by-side comparisons and share where to find similar items for less.
Lululemon says they protect their designs and signature details, such as trademarked color names like “Tidewater Teal.” The company claims that Costco has used the term and color in their marketing, adding weight to their argument that the knockoffs create consumer confusion.
“As an innovation-led company that invests significantly in the research, development, and design of our products, we take the responsibility of protecting and enforcing our intellectual property rights very seriously and pursue the appropriate legal action when necessary,” Lululemon said in a statement.
Legal experts say the company may face challenges in court. Alexandra Roberts, a professor of law and media at Northeastern University, said of one specific claim, “My first reaction as a trademark expert is that it looks pretty functional. I was just cracking up because that particular claim seemed really far-fetched to me. Those pants look really basic.”
Even so, Roberts acknowledged there could be stronger points in Lululemon’s case, especially if Costco’s actions contribute to consumer confusion or if marketing overlaps, suggesting an intentional connection to the Lululemon brand. Lululemon’s complaint references examples where Costco apparel bears a strong visual resemblance and similar product names, suggesting a pattern beyond mere coincidence.
Costco is not alone in the world of fashion dupes. Brands like Walmart and Quince have also come under the spotlight for offering budget versions of luxury items. While many of these products avoid legal trouble by avoiding exact replicas or trademark violations, the growing popularity of such lookalikes has made them a focal point in retail.
Lululemon has taken legal action over this issue before. In 2021, the company sued Peloton for alleged design infringement. That dispute eventually ended in a five-year partnership between the two companies.
The current lawsuit arrives at a time when Lululemon is under financial pressure. The company recently lowered their earnings forecast for 2025, citing weakening demand and tariff-related costs. Shares have fallen by 30 percent so far this year.
Retail analysts believe that while Lululemon defends their intellectual property, legal action might also have unintended consequences. Consumers unaware of the similarities may now turn to Costco’s alternatives, especially given the price gap.
The case will test how far a brand can go to protect their designs and identity in the retail industry. It also underscores the importance of clear brand differentiation. Relying solely on design or aesthetic to set a product apart may no longer be enough when competitors can mimic style at scale and with speed.
To stay competitive, companies must double down on what makes them distinct, whether proprietary materials, personalized customer experiences, or community-driven loyalty that imitators cannot easily copy.