New Balance has taken French sporting goods giant Decathlon to federal court, arguing that the backwards K stamped on Decathlon's Kiprun running shoes is close enough to New Balance's famous N to confuse shoppers and cost the Boston company money. The lawsuit, filed in the U.S. District Court for the District of Massachusetts, seeks damages, a jury trial, and an order forcing Decathlon to stop using the mark.
According to Reuters, New Balance has sued Decathlon in Massachusetts federal court, alleging that the mirrored K on Decathlon's Kiprun shoes resembles its famous N and will confuse consumers. The case is formally listed as New Balance Athletics Inc. v. Decathlon America LLC, case number 1:26-cv-14235, per the same outlet. Decathlon America is the U.S. affiliate of France-based Decathlon SE, a retailer that operates thousands of stores worldwide and, notably, also sells third-party sporting goods, including New Balance products, alongside its own house-branded lines.
New Balance says it has used an N on nearly all of its footwear since the 1970s, according to Boston.com. The company traces the mark back to 1976, when it launched its 320 running shoe — the first New Balance model to feature the distinctive N design, per the outlet's reporting. New Balance, a privately held company founded in 1906, describes the N marks as among its most valuable assets and says it owns several federally registered trademarks for the letter on footwear and other goods.
Notice Sent Months Before the Lawsuit
New Balance says it notified Decathlon of its concerns and asked the retailer to stop using the mark well before filing suit — Boston.com's report indicates the company put Decathlon on written notice in January, a detail also noted by Marathon Handbook. Decathlon refused, arguing that the design represents a K, not an N, the same Boston.com report states. Kiprun shoes went on sale in the United States on April 6 through Decathlon's website and specialty running retailers, according to Marathon Handbook, and the lawsuit now names eight Kiprun models sold to American customers, ranging from the $130 Kipsummit up to the $350 Kipstorm Lab.
The Kipstorm Lab has some running credibility behind it: Running Magazine describes it as a carbon-plated racing shoe that Kiprun athlete Jimmy Gressier of France wore when he set the European 5K record of 12:57 in March 2025. New Balance's own comparable racing shoe, the SC Elite, also got a new version in 2026, the same year Decathlon released an updated Kipstorm.
Post-Sale Confusion at the Heart of the Case
Part of New Balance's legal theory rests on what's known as post-sale confusion — the idea that shoppers might not be fooled at the register but could still mistake the shoes for New Balance gear once they're out in the world. As The Fashion Law explains, consumers may encounter the Kiprun design in those settings and mistake the shoes for New Balance products or believe there is some affiliation between the companies. The outlet notes that Chanel has used a similar post-sale confusion argument in prior litigation over allegedly counterfeit goods.
New Balance is not new to defending its N. The company previously filed and settled similar U.S. trademark lawsuits involving Michael Kors in 2021 and Nautica in 2019, according to SGB Online. Running Magazine also reports that a Chinese court awarded New Balance $1.5 million in damages and legal costs in 2017 over unauthorized use of its logo by other shoemakers, and that in 2019 the U.S. District Court for the District of Delaware found that New Bunren's stylized N marks infringed New Balance's trademarks.
What Comes Next
Barring an early settlement, the next procedural step in the case will be for Decathlon to file an Answer, according to Gerben Law. Spokespeople for both New Balance and Decathlon did not immediately respond to requests for comment on the lawsuit, per Reuters.
New Balance's financial figures underscore how much is riding on the outcome for a company built around a single letter. Boston.com reports the company took in more than $8 billion in revenue in 2025 and employs about 12,000 people globally, though Marathon Handbook cites a different figure, putting New Balance's 2025 revenue at $9.2 billion, a 19 percent jump — a discrepancy the available reporting does not resolve. Whatever the precise number, New Balance has framed the N as central to its identity for half a century, and it's now asking a federal court to decide whether Decathlon's K crosses the line.
