Shares of British drugmaker GSK dropped more than 9% on Monday, after a Delaware judge allowed more than 70,000 lawsuits alleging its discontinued heartburn drug Zantac caused cancer, to go forward.

GSK said it disagreed with the ruling and would immediately appeal.

Its shares were down 9.8% at 1,596 pence by 0727 GMT.

Following the ruling, analysts at J.P. Morgan said the potential liability that GSK could face from the litigation is likely higher than the $2 billion to $3 billion potential liability assumed by the market.

The judge ruled late on Friday that the expert witnesses can testify in court that the drug may cause cancer.

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However, former Zantac makers GSK, Pfizer, Sanofi and Boehringer Ingelheim had argued that the expert witnesses’ opinions lacked scientific support.

The lawsuits have been an overhang for the company, with concerns about protracted legal wrangling and compensation wiping almost $40 billion off the combined market value of GSK, Sanofi, Pfizer and Haleon over roughly a week in August 2022.