A farmer holds Monsanto's Roundup Ready soybean seeds at his family farm in Bunceton, Mo. Dan Gill/AP hide caption

itoggle caption Dan Gill/AP

Central Illinois corn and soybean farmer Gary Niemeyer readies his genetically modified seed corn for spring planting at his farm near Auburn, Ill. Seth Perlman/AP hide caption

itoggle caption Seth Perlman/AP

People march demanding labels for genetically modified food near the White House in Washington, D.C., on Oct. 16, 2011. Ren Haijun/Xinhua /Landov hide caption

itoggle caption Ren Haijun/Xinhua /Landov

Farmer Alan Madison fills a seed hopper with Monsanto hybrid seed corn near Arlington, Illinois, U.S. A group of organic and other growers say they're concerned they'll be sued by Monsanto if pollen from seeds like these drift onto their fields. Daniel Acker/Landov hide caption

itoggle caption Daniel Acker/Landov