Colloquially referred to as genetic scissors, the CRISPR-Cas9 system uses a protein (Cas9) and two RNA molecules to specifically cleave a target DNA sequence. This method of gene editing has become common in laboratory settings and is being used to develop promising new gene therapies, including some that are currently the subject of clinical trials. Broad and CVC each sought patent protection on CRISPR-Cas9 systems they studied and developed around 2012. The patents and applications resulted in the institution of four interference proceedings between the parties.
In a previous interference, Broad’s claims for a CRISPR-Cas9 system in eukaryotic cells were found to not interfere with CVC’s claims covering a generic CRISPR-Cas9 system. Broad was issued patents with claims to CRISPR-Cas9 systems for use in eukaryotic cells. CVC received broader claims that did not specify a cell type.
This case marks the second interference in the series to receive a decision from the PTAB. Here, there was no dispute that the CVC inventors were the first to invent a CRISPR-Cas9 system developed in vitro, i.e., outside of a cellular environment. CVC, however, also filed patent applications with claims covering a CRISPR-Cas9 system in eukaryotic cells. Those narrower claims were the focus of this second interference.
The focus of the PTAB’s decision was on whether the Broad inventors or the CVC inventors were the first to invent a CRISPR-Cas9 system designed for use in a eukaryotic cell. The PTAB found CVC’s evidence of its reduction to practice insufficient because the inventors did not recognize or appreciate that those experiments were successful. Instead, there appeared to be a recognition only that although the initial experiments could be impactful, the scientists’ description of the results did not indicate they were successful and the scientists stopped pursuing those experiments. Accordingly, the PTAB found that the evidence failed to show that the CVC inventors and their collaborators considered the experiments to be successful, and, as a result, the experiments could not constitute an actual reduction to practice.
The PTAB also found CVC’s evidence of conception to be lacking. Specifically, the PTAB found CVC’s experimental designs insufficient because they were followed by a prolonged period of extensive research that included a number of failed experiments. According to the PTAB, the long series of experiments and discussions about potential ways they might change the system demonstrated that the CVC inventors did not know the solution for how to make their idea work. Thus, they did not have a permanent and definite idea of how to achieve the result at the alleged time of conception.
To support its reduction to practice date, Broad provided a manuscript it submitted to the journal Science and related correspondence that described experiments using a CRISPR-Cas9 system in eukaryotic cells. The PTAB found the correspondence between the inventors showed not just the inventors’ appreciation of their successful results, but also a recognition by others in the field that the experiments were successful. And the manuscript corroborated that the Broad inventors performed the experiments. Accordingly, the PTAB held that Broad was entitled to an actual reduction to practice as of the date of the manuscript.
Finally, addressing a derivation argument by CVC, the PTAB concluded that the Broad inventors could not have derived their work from CVC because CVC did not have a complete conception of the invention as of that time. Based on these determinations, the PTAB awarded priority to Broad.
Practice Tip: One takeaway from this decision is the stringency with which the PTAB reviewed CVC’s experimental results. The PTAB refused to credit certain experiments—which were arguably successful—as a reduction to practice because the inventors did not note the success at the time. Thus, when seeking to establish a conception and/or reduction to practice date, it may be important to identify evidence that indicates the inventors’ contemporaneous appreciation that the work was successful and did not require significant additional experimentation. For parties who are actively engaged in research and development, it may be worthwhile to identify even those small successes in experiments where the overall results are mixed.
Regents of Univ. of California v. Broad Institute, Inc., Patent Interference No. 106,115 (PTAB Feb. 28, 2022)