LINCOLN, Neb. (DTN) -- Bayer alleges AIG Property Casualty Co. has repeatedly refused to honor liability insurance policies the company bought between 1967 and 1986 that cover losses in Roundup litigation, in a multi-billion-dollar lawsuit filed by Bayer in the Circuit Court of St. Louis County in Missouri.

About 149,000 plaintiffs have filed more than 56,000 lawsuits alleging Roundup causes non-Hodgkin's lymphoma, resulting in Bayer paying more than $10 billion in settlements.

All the while, Bayer told the court, AIG continues to refuse payment "many months" past the time periods they were obligated to pay on the policies.

"Old Monsanto timely paid all premiums and old Monsanto and/or Monsanto satisfied all terms and conditions and/or prerequisites to coverage for the underlying claims under the AIG policies," the lawsuit said.

"Monsanto has satisfied its duties of cooperation under the AIG polices as well as all other policy conditions that are potentially applicable with respect to obtaining coverage for the underlying claims. The documents and other information that Monsanto provided to the AIG insurers confirm that Monsanto's demands set forth above are covered by, and/or are otherwise in conformity with, the subject AIG policies."

In addition, Bayer alleges AIG also has not paid out claims on more than $1.9 billion in settlements reached on PCB claims. PCBs, or polychlorinated biphenyls, are chemicals used in manufacturing.

The Bayer lawsuit was filed as the company also continues to wait for a decision from the Supreme Court on the company's petition filed on state and federal labeling laws and their effect on future Roundup litigation. See more about that here: https://www.dtnpf.com/….

The AIG insurance covers the period during which alleged injury and exposure to Roundup occurred, according to the lawsuit. The Roundup lawsuits started around 2015. Liability insurance policies are written as occurrence policies, meaning they cover damages from incidents that occurred during the policy period.

Bayer asked the court to declare AIG must cover defense and settlement costs on the claims until policy limits are exhausted. The company also is seeking compensation for AIG's failure to pay and has asked for a jury trial.

The policies at question are excess liability policies that pay only after underlying insurance is exhausted. The actual amount AIG owes, according to the lawsuit, depends on how costs are allocated across all of Bayer's insurance policies.

According to Bayer's complaint, the policies require payment within 30 to 60 days of demand. However, AIG refused demands made by Bayer on glyphosate in July, October and December in 2024, Bayer alleges in the lawsuit.

"The AIG insurers have engaged in a relentless pattern of making meritless excuses and contending that, despite the documents that Monsanto has produced and the other information that Monsanto has otherwise provided, they do not have enough information to determine coverage," Bayer said in the lawsuit.

"The AIG insurers attempted to justify their refusals by asserting numerous meritless excuses and purported defenses."

AIG declined to comment on this article.

Todd Neeley can be reached at todd.neeley@dtn.com

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