Brand Clash Heats Up as Lululemon Sues Costco Over Imitation Yoga Apparel

• Lululemon has filed a lawsuit against Costco, claiming striking similarities in the design of two of its signature clothing items.
• The outcome could set a precedent for how fashion brands worldwide protect their designs and navigate competition in an increasingly crowded market.

A Brand Clash Worth Watching

As a fashion editor, I’ve covered plenty of spats between designers, but this one caught my attention because of who’s involved and what’s at stake. When Lululemon—a brand that helped shape the premium athleisure space—goes head-to-head with Costco, a giant in bulk retail and no-frills private labels, it marks a clash between two distinct worlds of fashion economics.

This lawsuit isn’t just about legalities—it reflects a much bigger story about where fashion, branding, and consumer perception all meet. As a fashion editor, I’ve seen plenty of disputes over design rights, but this one stands out—not just because of what’s being argued, but because of who is involved. On one side, there’s Lululemon, practically a symbol of upscale athleisure. On the other, Costco—a retail powerhouse built on bulk buys and no-frills private labels.

A Legal Battle Over Signature Designs

Lululemon has taken Costco to court over what it describes as unauthorised replication of two of its most popular garments. The legal complaint, filed in California, accuses Costco’s Kirkland Signature brand of marketing products that closely resemble Lululemon’s ABC pants and Define jacket—two designs that have become central to Lululemon’s identity and commercial success.

The Products at the Centre of the Dispute

You will find Lululemon’s ABC pants everywhere—and for good reason. Designed for men who want the smart look of chinos but the comfort of gym wear, they’ve become a staple. For women, the Define jacket hits a similar sweet spot. Its fitted shape and technical fabric make it as popular for running errands as it is for workouts. These pieces aren’t just customer favorites—they really capture what Lululemon is all about. In fact, they’ve played a big part in helping the brand hit $9.6 billion in global revenue by 2024.

Lululemon’s Allegations Against Costco

Lululemon says Costco crossed a line. Their complaint? That the Kirkland yoga gear looks way too much like Lululemon’s — same seam placement, same general vibe. Not just inspired by, but nearly indistinguishable, they argue. And that’s a problem. Shoppers might think it’s the same quality, the same brand even. Which, according to Lululemon, undercuts everything they’ve built — years of design work, branding, research, and money. So now, they’re not just asking for cash. They want the courts to put a stop to it entirely.

The Broader Brand Implications

Lululemon’s not just worried about making less money. What really seems to matter is the image they’ve spent over 20 years building. A brand rooted in wellness, good design, and trust—that’s the story they’ve been telling. And now, they feel that story’s being challenged. Its wide customer base engages not only with its products but also with the broader lifestyle positioning it wants to integrate within people who are not just into fitness but prefer comfortable athleisure cloathing. That investment is harder to quantify but just as central to its long-term strategy.

A Legal Grey Area in Fashion Design

Unlike logos or trademarks, garment silhouettes and features and styles  are not always protected by clear-cut laws, particularly in jurisdictions like the U.S. Lululemon’s lawsuit leans heavily on the “look and feel” argument—a concept that’s more interpretive and less settled in legal precedent.

In Europe and some parts of Asia, fashion design rights can be registered and enforced with more clarity. But globally, there seems to be a lacking in a single framework, which complicates cross-border brand protection.

How Brands Respond to Design Replication

For many global fashion labels, the risk of copycat products is an ongoing concern. Successful items tend to inspire similar designs, we see this time and again with products of major brands being ripped off to produce copies that are oddly similar,, but when competitors offer nearly indistinguishable versions at lower prices, legal action becomes more likely. The Lululemon-Costco case illustrates the thin line between inspiration and imitation, and the high stakes involved when brands feel that line has been crossed.

Costco’s Position in the Market

Kirkland Signature is known for simplicity, price accessibility, and scale. For many it comes across as the more affordable option.  Costco often introduces private label versions of popular products, appealing to value-driven customers. This approach has done a lot to boost Costco’s presence in the apparel game, even if the brand isn’t exactly known for design originality. So far, Costco hasn’t said anything publicly in response to Lululemon’s claims—they’ve stayed quiet. It’s unclear whether the brand will choose to defend the design of its items or seek a quick and less messy resolution out of court.

The Consumer Angle

Here’s the thing: not everyone shops the same way. Some swear by the brands they’ve worn for years — it’s emotional, familiar. Others are more practical. If it looks good and costs less, why not? That’s how a lot of people see it. And yeah, quality and ethical stuff matter, of course. But at the end of the day, for many folks, price is what really pushes them to make a choice.

Strategic Lessons for Global Brands

This case sends a clear message to companies across the fashion and lifestyle sectors: distinct product design is a strategic asset. Protecting that asset requires significant  vigilance, a clear legal strategy, and ongoing brand differentiation. It also means educating consumers on what sets your products apart—not just in look, but in feel, performance, and origin.

A Potential Turning Point for Fashion IP

The court’s decision could establish a broader precedent. If Lululemon prevails, brands may become more assertive in policing their visual identities. If Costco prevails, it may reinforce the difficulties of using the legal system to defend product aesthetics in the absence of explicit trademark protections. Major fashion brands will have their eyes peeled on the proceedings given the amount of “inspiration” is often derived from key “most selling” products.

With home marketers and instagram sales becoming all the rage, rip-offs of designs is becoming more and more common.

Final Word: A Cultural Moment in Apparel

This lawsuit is more than a courtroom dispute—it’s a signal that in today’s crowded marketplace, brand authenticity and design originality are under constant pressure. As someone immersed in fashion editorial, my perspective on this case study in how modern brands must constantly reinforce their values, communicate their uniqueness, and be ready to defend both.

No matter on which side the verdict, this moment underscores that fashion isn’t just about what we wear—it’s about who we trust to make it.