Shares in German pharmaceutical group Bayer have dropped sharply following a US verdict linking a product to cancer. By mid-morning on Monday, Bayer's shares had lost 10.4% of their value.
Bayer owns agriculture giant Monsanto - which was ordered by a California judge on Friday to pay US$ 289m damages to a man who said ingredients used in a weed killer had caused his cancer.
Bayer says the product - glyphosate - is safe. It completed its US$ 66bn takeover of Monsanto in June. The landmark lawsuit was the first to go to trial alleging a glyphosate link to cancer.
The claimant, groundsman Dewayne Johnson, was diagnosed with non-Hodgkin's lymphoma in 2014. His lawyers said he regularly used a form of RangerPro while working at a school in Benicia, California.
The Californian jury said Monsanto should have warned users about the dangers of its Roundup and RangerPro weed killers. Mr Johnson is among more than 5,000 similar plaintiffs across the US.
Glyphosate is the world's most common weed killer. The California ruling could lead to hundreds of other claims against Monsanto.