Syngenta AG may file counterclaims against some of the more than 750 U.S. grain farmers and exporters who have sued the seed maker over sales of biotech corn seed that disrupted trading with China last year, regulatory documents show.

Syngenta, the world's largest crop chemicals company, is "assessing the scope for potential counterclaims" in response to lawsuits over Agrisure Viptera corn, also known as MIR 162, according to a filing with the U.S. Securities and Exchange Commission.

A company spokesman declined to comment on Friday due to "active litigation."

Last year, global grain handlers Cargill Inc and Archer Daniels Midland Co, along with hundreds of farmers, sued Syngenta for damages stemming from China's rejections of shipments of U.S. crops that contained Viptera corn.

At the time, the trait was approved for planting in the United States but not for import by China, a major corn buyer.

As of Jan. 28, 762 lawsuits had been filed, according to Syngenta's SEC filing on Thursday. The company says the claims are without merit.

Farmers and exporters accuse Syngenta of misleading the farm industry about the timeline for import approval by China and blame the company for a decline in U.S. corn prices. In April 2014, the National Grain and Feed Association estimated Beijing's rejections cost the U.S. agriculture industry at least $1 billion.

Additional farmers are still seeking to take legal action over alleged losses, said Don Downing, an attorney for Gray, Ritter & Graham who is a co-lead counsel for clients suing Syngenta.

"The idea that they would sue the very people they victimized, I'd be surprised," he said of the company.

Syngenta's consideration of counterclaims is "a lot of puffery," said lawyer Paul Hanly of Simmons Hanly Conroy, which is representing clients suing the seed maker.

"I'm really hard-pressed to see what the theory would be, other than some sort of disparagement claim," he said, adding that he believes a disparagement counterclaim would be baseless.

Representatives of Cargill and ADM did not immediately respond to requests for comment.

Late last year, China approved imports of Viptera corn.

Cargill then started selling seed containing the Viptera trait and scrapped a policy requiring farmers to provide advance notice for grain deliveries that may contain Viptera corn.

Lawsuits against Syngenta have been consolidated in Syngenta AG MIR162 Corn Litigation, U.S. District Court, District of Kansas, No 14-md-02591.