The EPO has rejected arguments filed in opposition to European patent No. EP2800811, titled "Methods and Compositions for RNA-Directed Target DNA Modification and for RNA-Directed Modulation of Transcription," jointly held by Dr. Emmanuelle Charpentier, the regents of the University of California, and the University of Vienna.

The ruling affirmed the patentability of the inventions described.

The decision was made after three days of hearings. Most of the original 23 claims remained intact, with the two minor modifications having virtually no impact on the broad coverage of the patent.

"The outcome of the opposition hearing reinforces the broad and fundamental nature of this patent," stated Eric Rhodes, CEO of ERS Genomics, in a press release. "This result, combined with the recent EPO Technical Board of Appeal decision upholding the full revocation of the Broad Institute's patent EP2771468, viewed as its foundational CRISPR-Cas9 patent in Europe, further solidifies our position as holding the predominant CRISPR/Cas9 patent portfolio."