(Bloomberg) -- Sanofi defeated Boehringer Ingelheim GmbH in an arbitration proceeding over legal responsibilities tied to controversial heartburn medicine Zantac.

The French drugmaker is not liable to indemnify BI for any potential losses related to ongoing Zantac litigation in the US, where thousands of plaintiffs have alleged that the heartburn medicine causes cancer, according to a statement Tuesday. Sanofi shares rose as much as 2.5% in Frankfurt.

The decision further reduces Sanofi’s exposure in the Zantac litigation after a US federal court in December rejected the scientific evidence behind plaintiffs’ claims. Despite that court ruling, companies including GSK Plc, AstraZeneca Plc, Sanofi and BI still face as much as $7 billion in potential settlement costs related to tens of thousands of lawsuits outstanding in US state courts, according to Bloomberg Intelligence.

The arbitration arose out of a 2017 transaction in which Sanofi swapped its animal-health business for BI’s consumer-health care business. Sanofi insists that Zantac — which GSK first brought to market in the US in 1983 — is safe.

BI declined to comment, saying the arbitration decision is confidential.

(Updates with shares, Boehringer declining to comment)

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