The PTAB Reaffirms Priority Decision for CRISPR IP

On March 26, 2026, the U.S. Patent Office’s Patent Trial and Appeal Board (PTAB) reaffirmed its prior determination that the Broad Institute has priority over the University of California for the invention of a single-guide CRISPR-Cas9 system for eukaryotic gene-editing.

Last May, in Regents of the University of California v. Broad Institute, Inc. (Fed. Cir. 2025), the Federal Circuit vacated and remanded the PTAB’s prior decision.

On remand, the PTAB reconsidered whether the University of California inventors were the first to conceive a complete and operative embodiment of a single-guide CRISPR-Cas9 system for eukaryotic gene-editing, and, if so, whether the University of California inventors exercised reasonable diligence in reducing the invention to practice or communicated the conception to the Broad inventors.[1]

Conception

The Federal Circuit asked the PTAB to consider whether the University of California’s team, led by Jennifer Doudna, had formed the idea for a single-guide CRISPR-Cas9 system for eukaryotic gene-editing in a “sufficiently final form that only the exercise of ordinary skill remained to reduce it to practice.”[2]

The Federal Circuit explained that, in arriving at the previous priority decision, the PTAB had failed to properly consider:

1. whether a person of ordinary skill in the art could have reduced the invention to practice,

2. the experimental success of others on the record, and

3. whether the University of California successfully described the routine methods in the disclosure at the conception date and whether routine methods were used in successful editing of eukaryotic cells with a single-guide CRISPR-Cas9 system.[3]

The Federal Circuit instructed the PTAB to apply the proper legal framework and to consider the previously unconsidered evidence as to whether routine skill could bridge the gap between conception and practice.

Here, the University of California argued that routine gene-editing techniques were used to adopt the in vitro CRISPR-Cas9 system they published in 2012 for use in eukaryotes.[4] As evidence, the University of California provided expert testimony regarding successful experiments by third-party labs.[5] Broad argued, to the contrary, that modifications and substantial experimentation were needed to adapt the in-vitro system described by the University of California inventors to edit a eukaryotic genome.[6] The PTAB compared the labs that successfully edited eukaryotic genomes with CRISPR-Cas9 based on the in-vitro experiments and those that did not, noting that the successful labs had “capabilities superior to those of the ordinary skilled artisan.”[7] The PTAB concluded that “the ordinarily skilled artisan would have required some instruction or explanation of the necessary conditions or would have had to undertake extensive research or experimentation to make an operative eukaryotic CRISPR-Cas9 system.”[8]

The University of California also argued that because it reduced the invention to practice using the same vectors, reagents, strategies, and techniques originally disclosed in the application, conception was complete before Broad reduced the invention to practice.[9] The PTAB, however, agreed with Broad’s argument that the University of California inventors were exploring options for implementing the system. According to the PTAB, the University of California inventors did not have “a definite and permanent idea of what was necessary to achieve [a] CRISPR-Cas9 system[] capable of cleaving or editing target DNA in a eukaryotic cells” at the proposed conception date.[10]

The PTAB concluded that the University of California had “not met its burden of showing its inventors conceived [the invention] before Broad’s reduction to practice.”[11]

Derivation

The University of California’s claim of derivation was likewise unsuccessful because the University of California was unable to demonstrate that its inventors conceived of the claimed subject matter before Broad.[12]

The decision preserves the priority standing of Broad’s 13 issued patents and one application over the University of California’s 14 applications involved in this interference.

What’s next

• Other parties claiming interests in early CRISPR IP—such as Sigma-Aldrich and ToolGen—can now renew their challenges against the Broad Institute.

[1] See Regents of the Univ. of Cal. v. Broad Inst., Inc., Patent Interference No. 106,115, Paper 2915 (P.T.A.B. Mar. 26, 2026).

[2] Id. at 13, citing Regents of the Univ. of Cal. v. Broad Inst., Inc., 136 F.4th, 1367, 1380 (Fed. Cir. May 12, 2025).

[3] Regents v. Broad, Patent Interference No. 106,115, Paper 2915 at 4.

[4] Id. at 12 and 21.

[5] Id. at 12 and 21.

[6] Id. at 26.

[7] Id. at 33.

[8] Id. at 19.

[9] Id. at 38.

[10] Id. at 42–43.

[11] Id. at 48–49.

[12] Id. at 50.