Federal Circuit Clarifies Standard for Patent Conception in Ongoing CRISPR Dispute
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On May 12, 2025, the U.S. Court of Appeals for the Federal Circuit issued a long-awaited decision in Regents of the University of California v. Broad Institute (Nos. 22-1594, 22-1653) addressing priority for disputed CRISPR-Cas9 patents dating back to 2012. The court partially vacated and remanded the Patent Trial and Appeal Board’s (PTAB) decision awarding priority to the Board Institute for certain gene-editing patents, holding that the PTAB erred by requiring the inventors “to know their invention would work to prove conception.” This decision raises questions about the legal test for conception, which is critical for patent priority under the pre-America Invents Act first-to-invent system.
CRISPR Technology
CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats) refers to natural gene-editing capabilities found in simple organisms like bacteria. Scientists have been adapting CRISPR for gene-editing applications that might cure human diseases. The current technology has two essential components; 1) a guide RNA that matches the target gene for editing, and 2) a Cas9 protein that acts as molecular scissors, cutting the target DNA at a specific location. Researchers are already applying CRISPR to correct disease-causing genetic mutations, create disease models, and develop new cell therapies. Emmanuelle Charpentier and Jennifer Doudna won a 2020 Nobel Prize for developing the “CRISPR/Cas9 genetic scissors.”1
The Long-Running Dispute Over Patent Priority
For years, two research groups have contested entitlement to CRISPR patent priority dates: the Regents of University of California, the University of Vienna, and Emmanuelle Charpentier on one hand (the “Regents”), and the Broad Institute, Harvard University, and MIT on the other (“Broad”). Both groups filed patent applications dating back to 2012, eventually leading to multiple interference proceedings at the PTAB.
This appeal addressed one of those interferences, where the PTAB previously awarded priority to Broad after determining that the Regents’ inventors failed to demonstrate an earlier conception date because they did not know whether their work on prokaryotes (single-celled organisms such as bacteria) would translate to eukaryotes (more complex organisms like humans).2
The Federal Circuit’s Analysis of Conception
One year after hearing oral argument, the Federal Circuit (Judges Reyna, Hughes, and Cunningham) vacated the PTAB’s decision due to legal errors in determining conception and remanded the issue for further consideration. Generally, conception depends on “whether the inventors had a definite and permanent idea of the operative inventions.”3
First, the panel held the PTAB legally erred by “requiring Regents’ scientists to know that their invention would work” to demonstrate earlier conception.4 That conflated the “distinct legal standards for conception and reduction to practice.”5 Early on, “an inventor need not know that his invention will work for conception to be complete.”6 Alternatively, knowledge that the invention will work “can rest only on an actual reduction to practice.”7 Therefore, it was incorrect to “focus [] on Regents’ scientists’ statements of uncertainty, without considering whether those statements led to modifications in their experiments that substantively changed their original idea.”8
Second, the Federal Circuit held that the PTAB should have analyzed whether a person of ordinary skill in the art could have put the invention into practice when determining conception. The key issue was “whether [Regents’ scientists] had formed the idea of [the invention’s] use for [its intended] purpose in sufficiently final form that only the exercise of ordinary skill remained to reduce it to practice without extensive research or experimentation.”9 Experimental difficulty10 or success11 by third parties is relevant. Also relevant is whether the “alleged inventor contemplated the use of routine skill or methods at an asserted conception date, or used such routine skill or methods during subsequent, successful experimentation conducted by the alleged inventor.”12 Accordingly, the PTAB should have weighed Regents’ evidence of other researchers’ experimental success.13
Separately, the Federal Circuit also upheld the PTAB’s decision that certain Regents’ patent applications failed the written description requirement and dismissed a Broad cross-appeal on claim construction as moot.
Key Takeaways
- Although this decision opens the door for Regents to gain priority, uncertainty remains. The PTAB proceedings will continue following the Federal Circuit’s guidance, subject to potential requests for further appellate review.
- Patent litigants might try to argue that the legal test for conception has shifted. The Federal Circuit emphasized that inventors need not know that their inventions will work to prove conception. Additionally, evidence of others’ failures or successes must inform the scope of “routine skill or methods.” This could affect priority disputes for pre-AIA patents.
- This dispute may affect other disputes on CRISPR patents around the world, including pending interferences involving ToolGen and Sigma-Aldrich. CRISPR-related patent filings and proceedings are continuing in Europe.
1 https://www.nobelprize.org/prizes/chemistry/2020/press-release/.
2 Regents of the Univ. of Cal. v. Broad Inst., Inc., Patent Interference No. 106,115 (PTAB Feb. 28, 2022).
3 Regents of the Univ. of Cal. v. Broad Inst., Inc., Nos. 22-1594, 22-1653 (Fed. Cir. May 12, 2025), slip op. at 17.
4 Id. at 16.
5 Id.
6 Id. (quoting Burroughs Wellcome Co. v. Barr Lab’ys, Inc., 40 F.3d 1223, 1228 (Fed. Cir. 1994)).
7 Id. (quoting Applegate v. Scherer, 332 F.2d 571, 573 (CCPA 1964)).
8 Id. at 17.
9 Id. (citing Burroughs, 40 F.3d at 1228, 1231 (quotations omitted)).
10 Id. (citing Amgen, Inc. v. Chugai Pharm. Co., 927 F.2d 1200, 1207 (Fed. Cir. 1991)).
11Id. at 18 (citing Brand v. Thomas, 96 F.2d 301, 303 (CCPA 1938)).
12 Id.
13 Id. at 20.
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