On June 3, 2020, the U.S. Court of Appeals for the 9th Circuit granted the requests of the National Family Farm Coalition, the Center for Food Safety, the Center for Biological Diversity and the North American branch of the Pesticide Action Network to revoke the authorizations for dicamba-based crop protection products granted on October 31, 2018 by the Environmental Protection Agency (EPA).
In 2016, the American company Monsanto obtained a two-years long authorization from the EPA to produce and market several crop protection products based on dicamba, an organochlorine weedkiller. This authorization was conditional on Monsanto's compliance with various rules relating to product safety. These included an obligation to limit any "off-site" release of dicamba, i.e. any release of dicamba beyond the plots directly targeted by the treatment. However, during the 2017 and 2018 spraying campaigns, numerous discharge incidents were reported: 1,287 incidents were reported in 2017 and around 1,400 in 2018. Despite this finding, and Monsanto's manifest inability to guarantee the absence of off-site dicamba releases, in a decision dated October 31, 2018 the EPA decided to again renew registrations for XtendiMax (Monsanto-Bayer), Engenia (BASF),and FeXapan (Corteva).
Due to the closure of California’s courts during the coronavirus pandemic, the trial was held by telephone on April 21, 2020. In grounds for setting aside the October 31, 2018 registration decision, the Court of Appeal noted that the EPA had underestimated the amount of dicamba used, and misjudged the "unprecedented" damage caused by off-site releases. The EPA was also negligent in failing to recognize the risk that the use restrictions imposed on dicamba might not be respected. The cancellation runs from June 3, 2020, and farmers have until July 31 to dispose of existing stocks.
Following this decision, the EPA issued an order allowing spraying to continue until July 31. Farmers' and environmental groups then petitioned the Ninth Circuit Court of Appeals on June 11 to convict EPA Administrator Andrew Wheeler of refusing to comply with a federal court ruling suspending the use of the pesticide dicamba. The manufacturing companies also challenged the order. All these claims were dismissed by the court.
However, on October 27, 2020, the EPA registered Xtendimax, Engenia and Tavium marketed respectively by Bayer, BASF, and Syngenta, until December 2025, solely for applications on dicamba-tolerant cotton and soybean crops. Mr. Wheeler said the new restrictions on when the herbicide can be sprayed will solve the problems raised by the Ninth Circuit. These registrations have again been the subject of litigation (see CBD et al. vs. EPA et al., No. 4:20-cv-00555-DCB).