LONDON — A group litigation involving 7,111 claimants who allege that talcum baby powder sold by Johnson & Johnson caused cancers opened at the High Court in London on Wednesday. The case is set to become the largest product liability case in UK history, having grown from an initial 3,000 claimants.

All of the claimants have cancers, including ovarian cancer and mesothelioma, that they allege are linked to asbestos exposure from the product. The claim, filed in October 2025, alleges that Johnson & Johnson was aware as early as the 1960s that its talcum powder contained contaminants linked to cancers, and that the company never issued warnings on the packaging, instead marketing the product as a symbol of purity and safety.

Johnson & Johnson denies knowingly selling baby powder contaminated with asbestos. "The baby powder was compliant with any required regulatory standards, did not contain asbestos, and does not cause cancer," the company said. The sale of baby powder containing talc stopped in the UK in 2023.

The hearing is focusing on how the litigation will proceed through court. Both sides agree that group litigation is acceptable, but disagreements remain over procedural matters. KP Law, representing the claimants, called for the case to proceed more quickly, noting that one claimant is dying from cancer every three days.

"Some of the information the defendants are calling for serves no clear benefit and is tantamount to a full witness statement from each claimant," KP Law said. "Some requests are consistent with an intention to be onerous to the point of oppression and ultimately stifle the litigation."

Among the claimants was Margaret Manion, who was diagnosed with ovarian cancer in April 2024 and signed up to the claim later that year. She died in November 2025 at the age of 73. Manion said her mother had used baby powder on her as a baby, and she continued to use the talc every day as an adult, as well as on her own children.

"Her diagnosis was a shock, and the two years of her illness were the most painful experience ever, for Margaret and her family," Tony Bowden said. "She remained strong and resilient despite being well aware of the prognosis." The hearing is expected to conclude on Thursday, with a judgement at a later date.