The award was the latest in a series of court defeats for Monsanto over Roundup.
The company insists the glyphosate-based product is not linked to cancer.
The couple’s legal team described the damages award as “historic,” saying it totalled $2.055 billion after adding in slightly more than $55 million in compensatory damages.
“The jury saw for themselves internal company documents demonstrating that, from day one, Monsanto has never had any interest in finding out whether Roundup is safe,” said the plaintiff’s counsel Brent Wisner.
“Instead of investing in sound science, they invested millions in attacking science that threatened their business agenda.”
In a statement, Bayer said it was disappointed with the jury’s decision and would appeal the verdict, which it argues was at odds with a recent US Environmental Protection Agency review of glyphosate-based weed killers.
“The consensus among leading health regulators worldwide is that glyphosate-based products can be used safely and that glyphosate is not carcinogenic,” the statement read.
The verdict was the third courtroom defeat for Bayer in cases accusing the chemicals in Roundup of causing cancer.
Glyphosate developer Monsanto was convicted in the United States in 2018 and 2019 of not taking necessary steps to warn of the potential risks of Roundup — their weedkiller containing the chemical, which two California juries found caused cancer in two users.
“Unlike the first two Monsanto trials, where the judges severely limited the amount of plaintiffs’ evidence, we were finally allowed to show a jury the mountain of evidence showing Monsanto’s manipulation of science, the media and regulatory agencies to forward their own agenda despite Roundup’s severe harm to the animal kingdom and humankind,” said lawyer Michael Miller, who was co-lead trial counsel along with Mr Wisner.
Bayer announced last month more than 13,000 lawsuits related to the weedkiller had been launched in the US.