Bayer shares slide after Roundup cancer trial

It was a market reaction to a California court ruling last Friday when a dying groundskeeper was awarded damages of nearly $290 million, with the judges finding that Monsanto - now belonging to Bayer - should have warned buyers that its flagship Roundup weed killer could cause cancer.

Shares in Bayer AG (BAYRY) plunged more than 10% in early morning trade on Monday after Monsanto lost a case and looked set for more legal trouble in the near future.

Monsanto, which makes Roundup weedkiller, was ordered by a jury in a USA federal court in California to pay $289m (£226m) to a dying groundsman who said the product contributed to his cancer.

Monsanto, which also makes another similar product called Ranger Pro, has denied glyphosate is linked to cancer, saying hundreds of studies have found the product to be safe. There are now more than 5,000 similar lawsuits in the US against Monsanto's weed killers, according to Reuters, with Johnson's trial coming first because doctors claimed that he was close to dying. It says it will no longer use the Monsanto name.

Johnson's attorney Timothy Litzenburg told CNN that Monsanto's appeal will still prove costly for Bayer as the company will have to pay interest on the damages, believed to be about $25 million a year, while the court reviews its findings.

The firm, which is facing up to 5,000 similar court cases across the USA, said on Friday it would appeal against the verdict.