The Animal and Plant Health Inspection Service (APHIS) deregulated certain genetically engineered alfalfa plants. A number of organic alfalfa farmers, Geertson Seed Farms, among other parties, (plaintiffs) brought suit claiming that the APHIS decision violated the National Environmental Policy Act of 1969. The plaintiffs claimed that because of the ruling, they would have to incur significant costs to test their plants for contamination. They also claim that the ruling would require them to incur costs to decrease the likelihood that their plants are infected. The district court found in favor of the plaintiffs and granted permanent injunctive relief. The court of appeals affirmed. Monsanto (defendant) appealed, claiming, among other things, that the plaintiffs lacked constitutional standing to bring the claim. The United States Supreme Court granted certiorari.