Photo: The Canadian Press

Agribusiness company Monsanto has asked a San Francisco judge to throw out a jury's $289 million award to a former school groundskeeper who said the company's Roundup weed killer left him dying of cancer.

Attorneys for Monsanto said in court documents filed late Tuesday that DeWayne Johnson failed to prove that Roundup or similar herbicides caused his non-Hodgkin's lymphoma.

They said there was no evidence that Monsanto executives were malicious in marketing Roundup.

A jury last month determined that Roundup contributed to Johnson's cancer, and Monsanto should have provided a label warning of a potential health hazard.

It awarded Johnson $39 million in compensatory damages and $250 million in punitive damages.

Johnson's lawsuit is among hundreds alleging Roundup caused cancer.

His case was the first one to go to trial.