DuPont's Pioneer seed unit has sued Monsanto Co., claiming the company has infringed on patents that help genetically modified corn seeds germinate.

In its lawsuit, filed in United States District Court for the Southern District of Iowa, Pioneer Hi-Bred International claims that it owns patents on a method "of enhancing the vigor of maize seeds" by defoliating the plant at a particular point after pollination but before harvest, and on a maize seed and stand of maize seeds that have such enhanced vigor. The suit alleges that Monsanto has been using the methods protected by Pioneer's patents and seeks reimbursement by Monsanto for any profits gained from the sale of products made with the patents, as well as damages. 


Monsanto issued a statement following the lawsuit's filing, calling it "baseless" and "without merit," and said the approach covered by DuPont's patent is not used in any of Monsanto's production fields.

The case is Pioneer Hi-Bred International Inc v. Monsanto Co, No. 4:11-cv-00497.