Deposit Of Biological Material Is Not Always Necessary To Satisfy The Enablement Requirement If The Biological Material Is Known And Readily Available At The Time The Patent Is Granted

On November 18, 2025, an inter-partes review IPR2024-01014 between Inari Agriculture, Inc., Petitioner and Corteva Agriscience LLC, Patent Owner, received a Final Written Decision from the Patent Trial and Appeal Board asserting that no challenged claims were unpatentable of U.S. Patent 8,901,378 B2.

The '378 patent relates to an insect resistant corn plant TC1507, the DNA plant expression construct of corn plant TC1507, and the detection of the transgene/flanking insertion region in corn plant TC1507 and progeny thereof. The DNA construct is comprised of a DNA molecule named PH18999A capable of introduction into and replication in a host plant cell that, when expressed, confers insect resistance. The '378 patent discloses transforming maize with PHI8999A by particle bombardment and generating transgenic corn plants which express a B.t. delta-endotoxin Cry1F gene which provides insect resistance to the transgenic corn plants.

In an embodiment of the '378 patent, plants that survived the transformation with PHI8999A and were confirmed to express the Cry1F protein were subjected to a whole plant bioassay using European corn borer insects. Positive plants were crossed with inbred lines to obtain seed from the initial transformed plants. A number of lines were evaluated in the field. The TC1507 event was selected from a population of independent transgenic events based on a superior combination of characteristics, including insect resistance and agronomic performance.

Claim 1 is presented below.

1. A corn plant comprising a DNA construct, said DNA construct comprising a first and a second expression cassette, wherein said first expression cassette in operable linkage comprises

(a) a maize ubiquitin promoter;

(b) a 5′ untranslated exon of a maize ubiquitin gene;

(c) a maize ubiquitin intron;

(d) a Cry1F encoding DNA molecule; and

(e) a 3′ ORF25 transcriptional terminator; and said second expression cassette comprising in operable linkage

(i) a CaMV 35S promoter;

(ii) a pat encoding DNA molecule; and

(iii) a 3′ transcriptional terminator from (CaMV) 35S comprising the nucleic acid sequence of positions 5843 to 6032 of SEQ ID NO: 25;

and wherein the first and second expression cassettes are flanked by SEQ ID NO: 26 at the 5′ end and SEQ ID NO: 27 at the 3′ end.

The ‘378 patent issued from application No. 12/914,271 (“the '271 application”), filed on October 28, 2010. The '271 application claimed priority to several earlier applications, including application No. 11/774,236 (“the 2007 application”), filed July 6, 2007, which is a division of application No. 10/837,105 (“the 2004 application”), filed April 30, 2004, now Pat. No. 7,288, 643, published on February 16, 2006.

The Board ruled that it was undisputed that the 2004 application, the 2007 application, and the '271 application shared the same or substantially the same specification. It was also undisputed that Barbour, the sole alleged prior art, was the published 2004 application.

The Petitioner asserted a challenge to patentability based on the 2006 publication to Barbour which is before the 2010 filing date of the '271 application. Thus, Petitioner satisfied its initial burden to show that Barbour is prior art.

The burden of proof then shifted to the Patent Owner to show that Barbour is not prior art because the challenged claims are entitled to a priority date earlier than Barbour's 2006 publication date.

“[A] patent's claims are not entitled to an earlier priority date merely because the patentee claims priority.” In re NTP, Inc., 654 F.3d 1268, 1276 (Fed. Cir. 2011). “Rather, for a patent's claims to be entitled to an earlier priority date, the patentee must demonstrate that the claims meet the requirements of 35 U.S.C. § 120.” Id.; see also Nat. Alternatives Int'l, Inc. v.  Iancu, 904 F.3d 1375, 1380 (Fed. Cir. 2018) (holding that “claims in a patent or patent application are not entitled to priority under §120 at least until the patent owner proves entitlement to the PTO, the Board, or a federal court”). Under §120, entitlement to the benefit of an earlier priority date requires that the priority application satisfies the requirements under §112, which include, among others, the enablement requirement.

“Where an invention depends on use of living materials, such as microorganisms or cultured cells, it may be impossible to enable the public to make the invention solely by means of a written disclosure.” Wands, 858 F.2d at 735; see also In re Lundak, 773 F.2d 1216, 1220–21 (Fed. Cir. 1985) (“When an invention relates to a new biological material, the material may not be reproducible even when detailed procedures and a complete taxonomic description are included in the specification.”). “The deposit of biological organisms for public availability satisfies the enablement requirement for materials that are not amenable to written description or that constitute unique biological materials which cannot be duplicated.” Ajinomoto Co. v. Archer-Daniels-Midland Co., 228 F.3d 1338, 1345–46 (Fed. Cir. 2000). It is undisputed that Patent Owner did not make a deposit of the transgenic TC1507 germplasm. Thus, the enablement requirement is not met by deposit of living materials.

“Although inventions involving microorganisms or other living cells often can be enabled by a deposit, a deposit is not always necessary to satisfy the enablement requirement.” Wands, 858 F.2d at 736. “No deposit is necessary if the biological organisms can be obtained from readily available sources or derived from readily available starting materials through routine screening that does not require undue experimentation.” Id.; see also 37 C.F.R. § 1.802(b) (“Biological material need not be deposited . . . if it is known and readily available to the public or can be made or isolated without undue experimentation.”).

Based on the record available at that time, and for purposes of institution, the majority determined that Petitioner had shown sufficiently that the 2004 application did not meet the enablement requirement as of 2004, and thus, the challenged claims are not entitled to the 2004 priority date. Id. at 18–19.

After institution, Patent Owner continued to argue that “[i]t is sufficient to enable the claimed invention as of the filing date by depositing a seed or otherwise showing that the biological material is known and readily available by the issuance of the patent.” Patent Owner called attention to a 1987 Federal Register publication, setting forth the Office's position related to the deposit requirement. PO Resp. 16–18 (citing 52 Fed. Reg. 34080, 34081 (Sept. 9, 1987)).

In the Federal Register, the Office stated that "[i]f a biological material is known and readily available at the time the patent is granted, and there is no reasonable basis to believe that the biological material will cease to be available during the life of the patent, no requirement for a separate deposit would be made.” 52 Fed. Reg. 34080, 34081 (emphasis added). This statement supported Patent Owner's argument that, “[f]or claims where a biological sample may be required to enable the invention, enablement can be shown as of the filing date by depositing the material or otherwise stablishing it is ‘known and readily available' as of the date of issuance of the patent.” PO Resp. 17–18.

Patent Owner never made a deposit of the transgenic TC1507 germplasm. Instead, Patent Owner contended that “germplasm from TC1507 was known and readily available before the issuance of the '378 patent and remains so today, thus a deposit was not necessary. According to Patent Owner, “the disclosure originally filed in April 2004, coupled with Petitioner's admissions about the known and readily available TC1507 germplasm, enables the challenged claims under §112.” Specifically, Patent Owner argued that Petitioner argued for pages and pages, citing numerous exhibits and its own expert, that TC1507 was widely commercially available starting in 2003, that the source of TC1507— Herculex I—was well known and available from multiple sources, and that detection kits were identified in the IPR2024-01014 Patent 8,901,378 B2 14 application and were well known as commercially available such that one of ordinary skill in the art “could thus screen commercially available corn to identify germplasm expressing the TC1507 event, thereby possessing the claimed invention.”

In this case, it was undisputed that TC1507 germplasm was known and readily available to the public by Barbour's publication date in 2006 (Pet. 49–53), years before the 2014 issuance date of the '378 patent (Ex. 1001, code 45). Thus, based on the record developed through trial, the Board agreed with Patent Owner that the 2004 application satisfied the enablement requirement as of its application date in 2004. As a result, the Board found that the challenged claims were entitled to the 2004 priority date and, thus, Barbour did not qualify as prior art. Because all of Petitioner's challenges relied on Barbour, all those challenges failed.

Conclusion: After reviewing the entire record, the Board determined that Petitioner had not met its burden to show, by a preponderance of the evidence, that claims 1–8 of the '378 patent were unpatentable.

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