American farmers in three states are suing seed giant Syngenta AG in billion-dollar lawsuits, alleging that the company harmed U.S. corn markets when it released a new genetically altered strain of corn that wasn’t approved by Chinese authorities.

Three lawsuits filed on Friday from Sioux City, Iowa, Omaha, Nebraska and Springfield, Illinois allege that Syngenta “destroyed the export of U.S. corn to China and caused depressed prices for all domestic corn,” according to according to Courthouse News Service.

The product in question, Agrisure Viptera, also known as MIR162, is a corn seed that’s modified to protect against insects such as the corn borer and corn rootworm, which have evolved over the past few years to resist ordinary fertilizers. Syngenta released an original version in 2009 and another version this year.

While it was approved for production in the United States, Chinese regulators have yet to give it the green light, and have rejected more than 2,000 tons of corn imports this year.

The National Grain and Feed Association said earlier this year that American corn exports to China were just 171,000 tons between January and April, down 85 percent since the same period a year earlier.