The U.S. Supreme Court on Monday upheld Monsanto's biotech seed patents, dealing a blow to a group attempting to ward off lawsuits by the company against farmers.

The group, made up of 73 organic and conventional family farmers, seed companies and public advocacy interests, sued Monsanto in March 2011 seeking to prohibit the company from suing them if their fields became inadvertently contaminated with its patented genetic traits for corn, soybeans, cotton, canola and other crops.

The specialty seeds are genetically engineered to withstand dousings of glyphosate, the main ingredient in Monsanto's Roundup herbicide.

The group asked Monsanto for a pledge not to sue, but the company refused, saying: "A blanket covenant not to sue any present or future member of petitioners' organizations would enable virtually anyone to commit intentional infringement."

The biotech crops are widely used throughout the United States. Monsanto has sued more than 100 farmers for patent infringement, winning judgments against those found to have made use of its seed without paying required royalties.

The group lost in district court and in the U.S. Court of Appeals for the Federal Circuit.

"Monsanto never has and has committed it never will sue if our patented seed or traits are found in a farmer's field as a result of inadvertent means," said Kyle McClain, the company's chief litigation counsel.

"The lower courts agreed there was no controversy between the parties," McClain added, "and the Supreme Court's decision not to review the case brings closure on this matter."