The second cancer victim in a year to win a surprise victory against US pesticide maker Monsanto raises the prospect of a flood of similar lawsuits, potentially leaving the firm's new German owner Bayer with a major case of buyer's remorse.
From the toxic legacy of Monsanto's Roundup weedkiller to fears about its use of genetically modified seeds, here's what you need to know about the $63-billion (55.5-billion-euro) merger between Bayer and Monsanto.
Founded in Germany in 1863, Bayer is still best known for making aspirin. But more infamously, it briefly sold heroin in the early 20th century, which it marketed as a cough cure and morphine substitute.
During World War II, Bayer was part of a consortium called IG Farben that made the Zyklon B pesticide used in Adolf Hitler's gas chambers.
Through a series of acquisitions over the years, Bayer has grown into a drugs and chemicals behemoth and now employs some 100,000 people worldwide.
Much of its success in recent years was built on blockbuster drugs like Eylea—used to treat damage to the retina—or prostate cancer treatment Xofigo.
Monsanto was established in St. Louis, Missouri in 1901, setting out to make saccharine.
By the 1940s, it was producing farm-oriented chemicals, including herbicide 2,4-D which, combined with another chemical was used to make the notorious Vietnam War-era defoliant Agent Orange.
In 1976, the company launched probably its best-known product, the weed killer Roundup.
In the 1980s, its scientists were the first to genetically modify a plant cell. Monsanto then started buying other seed companies and began field trials of GM seeds.
It eventually developed soybean, corn, cotton and other crops engineered to be tolerant of Roundup.
Company bosses say that alongside applying big data to farmer's interventions on their crops, such resistant plant and pesticide combos will contribute to fatter harvests—needed to feed a world population expected to hit 10 billion by 2050.