A group of U.S. farmers is not giving up its fight against biotech giant Monsanto.

In the latest step of a two and a half year legal battle, plaintiffs in Organic Seed Growers and Trade Association (OSGATA) et al v. Monsanto asked the U.S. Supreme Court on Thrusday to hear their case challenging the patents on Monsanto’s genetically engineered seed.

The battle began in March 2011 when the farmers and seed companies brought a preemptive lawsuit against Monsanto to protect themselves from what they saw as unfair patent enforcement by Monsanto, whom they see as a “patent bully,” should the corporation’s genetically engineered seed contaminate the farmers’ crops. In other words, if these organic and conventional farmers are not using any Monsanto seed but their crops become contaminated (via wind, for example) with Monsanto seed, the farmers should not be slapped with a lawsuit by the corporation for patent infringement. As we reported earlier:

Their case was dismissed in February 2012 by Federal Judge Naomi Buchwald, but attorney Dan Ravicher of the not-for-profit Public Patent Foundation [which is representing the plaintiffs] said, “The District Court erred when it denied the organic seed plaintiffs the right to seek protection from Monsanto’s patents.” In July of 2012 the group filed an appeal to reverse the lower court’s decision…

In June of 2013, a three-judge panel at the Court of Appeals for the Federal Circuit dealt the farmers a blow in dismissing the case.

The June ruling stated:

Because Monsanto has made binding assurances that it will not ‘take legal action against growers whose crops might inadvertently contain traces of Monsanto biotech genes (because, for example, some transgenic seed or pollen blew onto the grower’s land),’and appellants have not alleged any circumstances placing them beyond the scope of those assurances, we agree that there is no justiciable case or controversy,”

However, Reuters reported that “Monsanto has sued more than 100 farmers for patent infringement, winning judgments against farmers found to have made use of its seed without paying required royalties.”

“While the Court of Appeals correctly found that the farmers and seed sellers had standing to challenge Monsanto’s invalid patents, it incorrectly found that statements made by Monsanto’s lawyers during the lawsuit mooted the case,” Daniel Ravicher, Executive Director of the Public Patent Foundation (PUBPAT) and lead counsel to the plaintiffs in OSGATA et al v. Monsanto, said in a statement on Thursday. “As a result, we have asked the Supreme Court to take the case and reinstate the right of the plaintiffs to seek full protection from Monsanto’s invalid transgenic seed patents.”

Jim Gerritsen, president of the lead plaintiff OSGATA and an organic seed farmer in Maine, has said, “We don’t want [Monsanto’s] seed. We don’t want their gene-spliced technology. We don’t want to have to defend ourselves from aggressive assertions of patent infringement because Monsanto refuses to keep their pollution on their side of the fence.”

In a statement on Thursday, Gerritsen added, “We believe we have the right to farm and grow good food the way we choose. We don’t think it’s fair that Monsanto can trespass onto our farm, contaminate and ruin our crops and then sue us for infringing on their patent rights. We don’t want one penny from Monsanto. American farmers deserve their day in Court so we can prove to the world Monsanto’s genetically engineered patents are invalid and that farmers deserve protection from Monsanto’s abuse.”

This article originally was published at Common Dreams.