This case study reviews a controversial court case that took place in Canada in 2002 concerning an allegation of patent infringement and a genetically modified (GM) canola crop. The multi-national company Monsanto, which produces GM canola seeds called Roundup Ready®, sued Saskatchewan farmer Percy Schmeiser for growing the crop on his farm without a contract. The defendant maintained that the crop seed blew onto his property without his knowledge. In this case study, students learn about the history of seed development and why we use pesticides in agricultural systems as well as the benefits and potential drawbacks of pesticides to society and the environment. They are then presented with the details of the court case and assigned stakeholder roles.  Each stakeholder group considers what the outcome of the court case means for their group. The case concludes with a class discussion in which each stakeholder group shares their views. Originally designed for an introductory environmental science course, the case could also be used in an introductory biology or genetics course.