Roundup is one of the most widely used weed killers in the world. It was originally developed by Monsanto and marketed for use in 1974 to manage weed growth across a variety of commercial and residential applications.

Glyphosate, the active ingredient in Roundup, was classified as carcinogenic in humans by the World Health Organization’s International Agency for Research on Cancer (IARC) in 2015. Other studies have linked glyphosate exposure to non-Hodgkin’s lymphoma and other cancers.

The IARC’s 2015 classification prompted a wave of litigation against Monsanto, as tens of thousands of plaintiffs accused the company of failing to warn about the risk of developing cancer associated with exposure to Roundup. The lawsuits were consolidated in multidistrict litigation in the Northern District of California in October 2016.

After losing three consecutive jury trials for combined damages of $191 million, Bayer AG, which acquired Monsanto in 2018, announced it will pay up to $10.9 billion to settle the vast majority of the current Roundup litigation – covering nearly 75% of the roughly 125,000 pending lawsuits, with an additional $4.5 billion set aside for future claims.