On June 11, 2025, the U.S. Court of Appeals for the Federal Circuit decided Agilent Technologies, Inc. v. Synthego Corp. (No. 23-2186), addressing enablement of prior art references for disputed CRISPR-Cas9 gene-editing patents. The court affirmed two Patent Trial and Appeal Board (PTAB) decisions that invalidated Agilent’s CRISPR patents, holding that key prior art was sufficiently enabled for invalidity purposes. The decision reiterates the distinction between the enablement requirements for challenged patents under 35 U.S.C. § 112 and for prior art under § 102.
Agilent's Patents and the PTAB's Decision
The patents at issue, Agilent's U.S. Patent Nos. 10,377,001 and 10,900,034, claim several chemical modifications at the ends of guide RNA (gRNA). The modifications improve stability and reduce degradation of gRNAs that are required for binding to the target DNA in the CRISPR-Cas9 gene-editing system. Synthego filed two petitions for inter partes review asserting that the patents’ claims were anticipated or rendered obvious by the "Pioneer Hi-Bred" patent application.i The PTAB found all challenged claims of both patents anticipated or obvious, and Agilent appealed.
The Federal Circuit's Analysis of Prior Art Enablement
On appeal, the Federal Circuit (Judges Prost, Linn and Reyna) held the PTAB properly found that Pioneer-Hi Bred was enabled and anticipated Agilent's patents.ii The court highlighted the standard for enablement of prior art references. Anticipation "does not require the actual creation or reduction to practice of the prior art subject matter; anticipation requires only an enabling disclosure."iii For prior art enablement, the reference "need not enable the [challenged] claim in its entirety, but instead the reference need only enable a single embodiment of the claim."iv There is also a presumption that prior art is enabling.v
First, the panel confirmed the PTAB's analysis that the Pioneer Hi-Bred reference was sufficiently enabled as prior art. The PTAB considered the Wands factors to assess whether undue experimentation was required and found that a person skilled in the art at the time could practice the disclosure in Pioneer Hi-Bred without undue experimentation. The PTAB also found that although some examples "in Pioneer Hi-Bred are prophetic, as opposed to working[] examples, that fact alone does not undermine the presumption that Pioneer Hi-Bred is enabled."vi
Second, Agilent argued that this case is analogous to Impax Labs., Inc. v. Aventis Pharms., Inc., 545 F.3d 1312 (Fed. Cir. 2008) and Amgen v Sanofi, 598 U.S. 594 (2023). The panel disagreed and distinguished both cases. In Impax, a prior art patent was not enabling since it "disclose[d] hundreds or thousands of compounds and several diseases," as well as "broad and general" dosage guidelines "without sufficient direction or guidance to prescribe a treatment regimen."vii Here, Pioneer Hi-Bred "recited chemical modifications at the recited locations and teaches that gRNA comprising such may be used as guide polynucleotides in a CRISPR Cas system."viii
The Federal Circuit also distinguished Amgen, noting that the "issue in Amgen was whether the asserted claims were sufficiently enabling to be valid under 35 U.S.C. § 112, not whether a prior-art reference was enabling and could thus support anticipation."ix There is a distinction since "[§] 112 'provides that the specification must enable one skilled in the art to "use" the invention whereas [35 U.S.C. §] 102 makes no such requirement as to an anticipatory disclosure.'"x In Amgen the asserted patent covered the "entire genus of antibodies that performed the claimed functions" and was not enabled.xi A person skilled in the art would have been "forced to engage in painstaking experimentation to see what works."xii The panel held that Pioneer Hi-Bred did not require such extreme experimentation as the person skilled in the art would understand the CRISPR system and the types of chemical modifications that can be made to gRNA from the disclosure.
Separately, the Federal Circuit also upheld the PTAB's obviousness decision because the prior art expressly discloses gRNA functionality and a skilled artisan would reasonably expect the chemical modifications to succeed.
Key Takeaways
- The case highlights the difficulty in overcoming the presumption that prior art is enabled. Prior art enablement arguments have rarely succeeded in recent years.
- Prophetic examples do not necessarily destroy the presumption that prior art is enabled.
- This is yet another example of the ongoing CRISPR disputes among multiple companies and universities. Last month, the Federal Circuit addressed priority for disputed CRISPR-Cas9 patents dating back to 2012 between the University of California and the Broad Institute.
i Synthego Corp. v. Agilent Techs., Inc., Nos. IPR2022-00402, IPR2022-00403 (P.T.A.B. May 17, 2023).
ii Agilent Techs., Inc. v. Synthego Corp., No. 23-2186, (Fed. Cir. June 11, 2025), slip op. at 12.
iii Id. (quoting Schering Corp. v. Geneva Pharms., 339 F.3d 1373, 1380 (Fed. Cir. 2003)).
iv Id. at 13 (quoting In re Morsa, 803 F.3d 1374, 1377 (Fed. Cir. 2015)).
v Id. (citing Impax Labs., Inc. v. Aventis Pharms., Inc., 545 F.3d 1312, 1316 (Fed. Cir. 2008)).
vi Id.
vii Id. at 14 (quoting Impax, 545 F.3d at 1315).
viii Id. at 15.
ix Id. at 16.
x Id. (quoting Rasmusson v. SmithKline Beecham Corp., 413 F.3d 1318, 1325 (Fed. Cir. 2005)).
xi Id. at 15 (citing Amgen, 598 U.S. at 602).
xii Id. (quoting Amgen, 598 U.S. at 614).
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