PTAB

IPR2023-01038

Bayer CropScience LP v. Corteva Agriscience LLC

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1. Case Identification

2. Patent Overview

  • Title: Herbicide Resistance Genes
  • Brief Description: The ’745 patent claims transgenic soybean plants and cells containing recombinant DNA that encodes an AAD-1 protein. This protein is defined by having at least 85% sequence identity to a specific sequence (SEQ ID NO: 9), containing a particular “AAD-1 motif,” and exhibiting enzymatic activity that degrades certain phenoxy auxin and aryloxyphenoxypropionate herbicides, thereby rendering the plant cells tolerant to them.

3. Grounds for Unpatentability

Ground 1: Claims 1-29 are anticipated by or, in the alternative, obvious over Corteva ’437

  • Prior Art Relied Upon: Corteva ’437 (International Publication No. WO 2005/107437).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the ’745 patent is not entitled to its claimed priority date of April 30, 2004. Instead, the earliest possible priority date is October 7, 2016, when the claims were first amended to include the specific "AAD-1 motif" and the "at least 85% sequence identity" limitation. Petitioner asserted that the predecessor applications lacked written description support for this claimed genus. This later priority date makes Corteva ’437—the Patent Owner's own international application published in 2005—invalidating prior art under 35 U.S.C. §102. Corteva ’437 allegedly discloses transgenic soybean plants expressing AAD-1 proteins (SEQ ID NO: 9-10) that fall within the scope of the challenged claims, including the required enzymatic activity and tolerance. As an alternative, Petitioner argued that if not anticipated, the claims are obvious over Corteva ’437 because anticipation is the epitome of obviousness.

Ground 2: Claims 1-6, 9-12, and 29 are obvious over Saari in combination with Schleinitz and Streber

  • Prior Art Relied Upon: Saari 1998 (a doctoral thesis) or Saari 1999 (a journal article), Schleinitz (Accession No. AF516751), and Streber (Patent 6,153,401).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground assumes, for the sake of argument, that the claims are entitled to the earlier April 30, 2004 priority date. Petitioner argued that the Saari references identified the RdpA protein (which the ’745 patent renames AAD-1) as capable of degrading the (R)-enantiomers of phenoxy herbicides and suggested its use in creating herbicide-resistant crops. Schleinitz disclosed the exact amino acid and nucleotide sequences for this RdpA protein, which corresponds to the patent's SEQ ID NO: 9. Streber taught the standard methods for achieving such transformations by successfully expressing a similar enzyme (TfdA) in plants to confer resistance to 2,4-D.
    • Motivation to Combine: A person of ordinary skill in the art (POSITA) would combine the teachings to practice the invention. Saari's suggestion to use RdpA for herbicide resistance would have directly motivated a POSITA to obtain its sequence from Schleinitz and apply the established plant transformation methods disclosed by Streber.
    • Expectation of Success: A POSITA would have a reasonable expectation of success because the prior art, particularly Streber, demonstrated that TfdA—an enzyme from the same α-ketoglutarate-dependent dioxygenase family as RdpA—had already been successfully expressed in crops to provide herbicide resistance.

Ground 3: Claims 7-8 and 13-28 are obvious over Saari, Schleinitz, and Streber in view of Jepson

  • Prior Art Relied Upon: Saari 1998 or Saari 1999, Schleinitz (Accession No. AF516751), Streber (Patent 6,153,401), and Jepson (Application # 2003/0041357).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground builds upon the combination in Ground 2 and adds the teachings of Jepson to address the dependent claims related to multiple herbicide resistance. Jepson disclosed transforming plants with multiple herbicide resistance traits, such as by combining a gene for phenoxy auxin resistance (like tfdA) with a gene for glyphosate resistance.
    • Motivation to Combine: A POSITA would be motivated to add Jepson's teaching to the primary combination to address the known problem of evolving herbicide-resistant weeds. Combining multiple resistance mechanisms was a known strategy for providing broader and more durable weed control. Therefore, a POSITA would have found it obvious to create plants expressing RdpA (from Saari/Schleinitz/Streber) and also containing a second herbicide resistance gene (e.g., for glyphosate) as taught by Jepson.
    • Expectation of Success: The combination was a simple application of known techniques (stacking resistance genes) to known elements (RdpA protein and glyphosate resistance genes) to achieve a predictable result (a plant resistant to multiple herbicides).

4. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial under §325(d) or Fintiv is inappropriate. The petition is based on prior art (Saari 1998) and arguments not presented to the examiner, and the examiner never considered the asserted combinations. Petitioner contended the examiner materially erred by failing to correctly determine the claims' priority date, leading to an improper patentability analysis. Regarding the Fintiv factors, Petitioner asserted that the co-pending district court case is in its early stages, with claim construction just beginning, and that Petitioner has stipulated not to pursue the same grounds in district court if an inter partes review (IPR) is instituted, thus avoiding duplicative efforts.

5. Relief Requested

  • Petitioner requests institution of an IPR and cancellation of claims 1-29 of the ’745 patent as unpatentable.