Confirms Cellectis’ Loss of Patent Protection for Single-Chain Meganucleases in Europe

RESEARCH TRIANGLE PARK, N.C.–Precision BioSciences, Inc., today announced that the Opposition Division of the European Patent Office (EPO) has issued a written decision confirming its November 18, 2009 revocation of the previously granted claims of Cellectis’ European Patent No. 1 485 475. As previously reported, after an oral hearing in an Opposition Proceeding initiated by Precision BioSciences, Cellectis’ previously granted claims to single-chain meganucleases, including those derived from I-CreI, as well as Cellectis’ claims to most classes of hybrid meganucleases, were revoked in their entirety. As a result of the interlocutory decision, Cellectis’ patent has been severely restricted such that it now includes only claims limited to hybrid meganucleases formed by the fusion of an N-terminal of the I-DmoI meganuclease to a domain derived from the I-CreI meganuclease.

“In fact, the remaining claims only cover certain hybrid meganucleases that, to my knowledge, are not currently in commercial use by anyone.”

“We are delighted with the written decision from the EPO’s Opposition Division. This confirms the oral decision issued last November, and should refute Cellectis’ bizarre assertion that the patent had been ‘upheld’ despite the revocation of the broad claims and the maintenance of only much narrower claims,” said Derek Jantz, Precision BioSciences’ VP of Scientific Development. “In fact, the remaining claims only cover certain hybrid meganucleases that, to my knowledge, are not currently in commercial use by anyone.”

“We take our legal right to practice our DNE technology very seriously and will continue to ensure that we are able to do so,” said Precision BioSciences CEO Matthew Kane. “Assuming the interlocutory decision is upheld on appeal, we are not aware of any third party patents that would preclude Precision BioSciences and its partners from practicing Precision’s next-generation DNE technology, including our custom-designed single-chain meganucleases, in Europe unfettered. Moreover, we look forward to the issuance of Precision BioSciences’ own patents directed to functional single-chain meganucleases and intend to enforce the claims of those patents vigorously,” he added. “Unlike Cellectis’ claims which were revoked in these proceedings, we believe that Precision’s pending claims are the first valid claims to single-chain meganucleases, and will provide Precision with a significant competitive advantage if issued in Europe and elsewhere,” said Mr. Kane.

Cellectis has the right to appeal the decision of the Opposition Division.

Interested parties can view the interlocutory decision of the EPO’s Opposition Division relating to EP 1 485 475 at: www.precisionbiosciences.com/news.

About Precision BioSciences

Precision’s mission is to utilize its engineered endonuclease technology to become the world leader in the field of genomic molecular biology. Precision’s proprietary Directed Nuclease EditorTM (DNE) technology enables the production of custom genome editing enzymes that can insert, remove, modify, and regulate essentially any gene in mammalian or plant cells.

Precision BioSciences has already produced hundreds of custom endonucleases for partners and internal development that can precisely alter naturally occurring sequences within genomes. Precision has successfully partnered its DNE technology with several of the world’s largest agbiotech firms and is internally developing applications in biological production and human therapeutics. For additional information, please visit www.precisionbiosciences.com.