WICHITA, Kan. (AP) - Another lawsuit has been filed against seed giant Monsanto over last month's discovery of an isolated field of genetically engineered wheat in Oregon. Kansas wheat farmer Dan Brown sued Monsanto on Tuesday on behalf of himself and potentially thousands of other growers. The Seward County resident's lawsuit is seeking class-action status. It's at least the third lawsuit filed against St. Louis-based Monsanto this month over the release of the experimental wheat. Kansas farmer Ernest Brown individually sued the company, and another lawsuit seeking class-action status was filed in Washington on behalf of growers of soft white wheat. Monsanto reiterated Wednesday that none of the genetically modified wheat entered the commercial market. The company says no legal liability exists given the care undertaken, and it vowed to present a vigorous defense.