You never expect your shoes to land you in court – but On is now facing a US class action over Cloudmonster sneakers that allegedly emit a “loud, embarrassing squeak” with every step.

Litigation sometimes arises for the strangest reasons. In this case, it’s the sound of your shoes. On is being sued in US District Court, Oregon, by plaintiffs Patricia Ramirez and Louis Bologna, who claim their Cloudmonster sneakers squeak with each step so loudly they’ve stopped wearing them, citing embarrassment and annoyance. Ramirez allegedly heard the squeak after just three uses; Bologna noticed it after three months.

The complaint goes further: it accuses On of being aware of the defect, refusing to issue returns or repairs, and excluding the alleged problem from its warranty coverage. It also cites social media posts, online reviews, Reddit threads, and DIY “fix-it” guides shared by frustrated users. According to court documents, the issue traces back to the CloudTec sole design, which includes hexagonal (or octagonal or oval) voids – purportedly an acoustic weakness. On has not publicly commented on the suit.

Why it matters

At first glance, a squeaky shoe might seem trivial – until consumers begin viewing premium price tags through that lens of “defects not covered.” For a brand built on performance excellence, this kind of issue cuts at its credibility. More broadly, the case could force greater transparency about what’s included in warranties, and how post-sale defects are handled. If a seemingly minor acoustics flaw can lead to litigation, competitors must reevaluate how they qualify, test, and support their own footwear systems.

Zooming out

The case fits into a larger trend in consumer goods: when brands push technical boundaries – light materials, novel foam designs, complex geometries – the unintended consequences may manifest in odd failure modes. In footwear, few class actions cover noise or sound defects, yet this may be a warning: variants of performance hybrids, cushioning systems, or sole geometries could all be scrutinized. In the highly competitive running and athletic footwear segment, where brand reputation matters deeply, a squeaky shoe becomes more than an annoyance – it’s a legal vulnerability. 

What to watch

  • How aggressively will On respond – whether via settlement, dismissal motion, or counterclaim.
  • Whether On issues a repair or recall program to quiet affected pairs.
  • If this inspires new class actions for other anomalous defects in sportswear and footwear.