A US judge will reduce an $US80 million ($A142 million) damages award against Bayer AG to $US50 million or less in the case of a man who blamed his cancer on glyphosate-based weed killer Roundup.
US District Judge Vince Chhabria in San Francisco said the jury's $US75 million punitive damages award to plaintiff Edwin Hardeman in March could not stand.
"It's quite clear that under the Constitution I'm required to reduce the punitive damages award and it's just a question of how much," Chhabria said during a court hearing in which lawyers for both sides discussed the company's request to overturn the verdict.
Following a four-week trial, a federal jury on March 27 awarded $5 million in compensatory and $75 million in punitive damages to Hardeman, who was diagnosed with non-Hodgkin's lymphoma in 2014.
US Supreme Court rulings limit the ratio of punitive to compensatory damages to 9 to 1.
Chhabria said he was also considering reducing the compensatory damages award because Hardeman was now in full remission and unlikely to suffer as much as he had in the past.
Bayer, which bought Roundup maker Monsanto for $63 billion last year, says Roundup's active ingredient glyphosate is safe for human use and not carcinogenic.
The company faces lawsuits by more than 13,400 plaintiffs nationwide and a series of Roundup jury verdicts against Bayer have prompted its share price to plummet.
Bayer had asked Chhabria to reverse the jury verdict in Hardeman's case in light of scientific evidence and assessments by regulators finding glyphosate to be safe.
But Chhabria disagreed, saying jurors had seen sufficient evidence that Monsanto did not care whether its products cause cancer, instead focusing on undermining people who were raising concerns.
Australian Associated Press