Agricultural biotechnology giant Monsanto recently marked an important victory in an intellectual property dispute with rival firm and DuPont subsidiary Pioneer Hi-Bred International. A court ruling ultimately upheld a Monsanto patent claim even though Pioneer was effectively first to file the original application.

According to Reuters, Pioneer was awarded a patent in July 2001 for a proprietary brand of genetically modified corn. Monsanto then filed a claim in 2005 suggesting that it had invented the underlying biotechnology to that seed in 1990. Pioneer asserted that its researchers had developed the concepts in June 1988 in its original filing. A lack of specificity in the official invention disclosure, however, has made their claims difficult to substantiate.

"Both parties filed motions to the [Board of Patent Appeals and Interferences] asking that the respective priority claims be denied," Dennis Crouch explained in a related post for PatentlyO. "The board sided with Monsanto - finding that Monsanto's patent claim drafted in 2005 properly claimed priority back to the 1990 filing document but that Pioneer's patented claim was not sufficiently disclosed in its 1988 application."

This week that verdict was once again confirmed in the U.S. Federal Court of Appeals. The case presents interesting questions regarding the burden of proof, according to Crouch, as Pioneer attorneys have asserted that courts may have shifted the onus more toward proving the 1988 claim instead of refuting the credibility of Monsanto's call for review.