Benitec said this week that the US Patent and Trademark Office has indicated that it is issuing a re-examination certificate for the company's core US patent, marking the final step in the agency's confirmation of the patentability of the claims within the intellectual property.
The patent, No. 6,573,099, essentially claims the knockdown of gene expression using DNA that transcribes double-stranded RNA. Although it was one of the earliest patents in the RNAi field, it was deemed invalid by the USPTO after re-examination proceedings were initiated by now-defunct expressed RNAi firm Nucleonics.
Nucleonics had been sued by Benitec for infringing the IP, but asked the patent office to review the patent as part of its efforts to fend off the patent-infringement suit. The case was ultimately dismissed, and late last year the USPTO reversed its invalidity ruling (GSN 11/11/2010).