World champion sprinter sues Puma and Mercedes F1 team over carbon-plate shoes

A product liability lawsuit brought by US world sprint champion Abby Steiner against Puma and the Mercedes-Benz Grand Prix Formula 1 team raises questions that extend well beyond one athlete’s career: whether carbon-plate footwear technology — now embedded across the entire running shoe industry — carries undisclosed injury risks, and who bears liability when it does.

The complaint, filed April 24 in Middlesex County Superior Court in Massachusetts, names Puma and Mercedes-Benz Grand Prix as co-defendants. Steiner alleges that footwear incorporating carbon fiber plate (CFP) and nitrofoam (NF) technology “alters the biomechanics of runners,” predisposing them to bone stress injuries and increased foot strain.

The lawsuit further claims both companies were aware of these risks yet continued to promote the products as safe without adequate inspection or disclosure. Shoes specifically cited in the complaint include the Puma Deviate Nitro Elite 2 and 3, and the evoSPEEDTokyo Nitro spikes.

Why is the Mercedes F1 team also named in this case?

Mercedes-Benz Grand Prix collaborated with Puma in developing performance footwear — a partnership the brand has publicly marketed as a competitive differentiator. The complaint states that both companies “were involved in and had control over the design, development, testing, manufacture, marketing, promotion, advertisement, sale, importation and distribution” of the footwear in question. That co-development arrangement, promoted as a marketing asset, has now become the basis for shared liability. The Mercedes-Benz Grand Prix team confirmed it has “nothing to comment re ongoing legal proceedings.”

A $2 million deal, a shattered career

Steiner is not an unknown athlete: she is a two-time World Athletics Championships gold medallist, four-time NCAA national champion, and the current US indoor record holder in the 200m and 300m sprints. She signed with Puma in July 2022 for a deal reportedly worth $2 million — an unusually large sum for a female sprint athlete transitioning from the college ranks. Within weeks of signing, she was part of the US teams that swept the 4x100m and 4x400m relays at the World Athletics Championships.

Injuries followed quickly. Steiner began experiencing foot problems in training, missed the 2023 World Athletics Championships entirely after surgery, and subsequently underwent at least three procedures between 2023 and 2025. At the 2024 US Olympic Trials, she finished sixth in the 200m, well short of making the Olympic team.

Under the constraints typical of active sponsorship agreements — which often limit athletes’ ability to speak directly with the media or discuss product concerns publicly — her communication about the experience came primarily through social media.

In 2025, she announced she would step back from competition to pursue a master’s degree in exercise science at the University of South Carolina. The complaint argues Steiner “only recently” established the causal link between Puma’s technology and her injuries — a framing intended to address any statute of limitations challenge to the late filing date.

This lawsuit could force the running-shoe industry to confront carbon-plate injury risks

The carbon-plate arms race in performance footwear began in earnest when Nike introduced its Vaporfly technology around 2017, delivering documented performance gains. Within a few years, virtually every major brand — Adidas, New Balance, Saucony, Hoka, and Puma among them — had developed carbon-plated racing shoes and spikes. The technology is now standard at elite competition level. Research has increasingly examined whether the biomechanical changes that make carbon-plate shoes faster also redistribute load in ways that increase injury risk for some athletes. No safety-focused regulatory framework governing CFP use in performance footwear currently exists.

Should Steiner’s legal team establish a causal link between CFP and NF technology and her injuries at trial, the implications for the category could extend to product-labelling standards, risk allocation in athlete endorsement contracts, and insurance exposure across multiple brands.

Steiner is seeking damages, and neither defendant has responded yet

Steiner is seeking financial and nonfinancial compensation including medical costs, lost career earnings and endorsement income, and what the complaint describes as “the loss of full enjoyment of life and disfigurement.” The damages amount will be determined at trial. As of April 28, neither Puma nor Mercedes-Benz Grand Prix had filed a court response or attorney appearance; a response is due by Aug. 24. Puma has not responded to media comment requests.