Boragen Inc v. Syngenta Participations AG

1. Case Identification

• Case #: IPR2020-00124
• Patent #: 10,130,096
• Filed: November 5, 2019
• Petitioner(s): Boragen, Inc.
• Patent Owner(s): Syngenta Participations AG
• Challenged Claims: 1-12

2. Patent Overview

• Title: Method for Protecting Useful Plants or Plant Propagation Material
• Brief Description: The ’096 patent is directed to a method for controlling fungal infestation of plants, plant propagation material, and/or harvested food crops. The method involves treating them with an effective amount of a specific oxaborole compound, 5-chloro-1,3-dihydro-1-hydroxy-2,1-benzoxaborole.

3. Grounds for Unpatentability

Ground 1: Claims 1-12 are obvious over Austin in view of Sibley.

• Prior Art Relied Upon: Austin (WO 1995/33754) and Sibley (WO 2009/130481).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Austin disclosed the exact 5-chloro benzoxaborole compound recited in claim 1 (as "compound 66") and taught its effectiveness as a biocide against various fungi, including plant pathogens. Sibley then explicitly taught using this same compound (identified as "AN2718") as an agricultural fungicide for "controlling a fungal disease in a plant," including application to foliage and seeds. The dependent claims, which add limitations such as carriers, treatment of seeds, and coloring agents, were also argued to be disclosed or suggested by Sibley's teachings on standard agricultural formulations.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine the references because both teach using the same boron-based compound as a fungicide. Austin provided the specific compound and its general biocidal properties, while Sibley provided the explicit motivation to apply that known fungicide in an agricultural context on living plants to control disease.
  • Expectation of Success: A POSITA would have a reasonable expectation of success because boron-based compounds were generally known as fungicides. More specifically, Sibley's teaching of the claimed compound's use as an agricultural fungicide confirmed its efficacy in the claimed method.

Ground 2: Claims 1-12 are obvious over Austin in view of Kohn.

• Prior Art Relied Upon: Austin (WO 1995/33754) and Kohn (Patent 3,686,398).
• Core Argument for this Ground:
  • Prior Art Mapping: As in Ground 1, Austin disclosed the claimed 5-chloro benzoxaborole compound and its general antifungal activity. Kohn, a 1972 patent, taught that structurally related boron compounds (boroxarophenanthrenes) are useful as fungicides and can be applied to "vegetative hosts such as plants, plant seeds, etc."
  • Motivation to Combine: A POSITA would combine Austin's specific, potent compound with Kohn's decades-old teaching of using structurally similar boron-based compounds for agricultural fungicidal purposes. Petitioner noted that the Patent Office Examiner relied on this same combination to reject the claims repeatedly during prosecution.
  • Expectation of Success: Success would be expected because both references teach using boron-based compounds to control fungi. Kohn provided the established utility of such compounds on plants, and Austin provided a newer, more potent compound within that class, making its application to plants a predictable step.
  • Key Aspects: This ground mirrored the Examiner's primary rejection during prosecution. Petitioner argued that the Patent Owner only secured allowance by submitting a flawed declaration that failed to compare the claimed compound to the most relevant prior art compound in Austin.

Ground 3: Claims 1-12 are obvious over Austin in view of Kohn and Baker.

• Prior Art Relied Upon: Austin (WO 1995/33754), Kohn (Patent 3,686,398), and Baker (Patent 7,582,621).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground augmented the Austin/Kohn combination with Baker. Baker disclosed that the claimed 5-chloro compound ("compound 2") and a nearly identical 5-fluoro compound ("compound 1") were potent antifungals for treating infections in animals.
  • Motivation to Combine: Baker's disclosure of the claimed compound's high potency against fungi on a living organism would have motivated a POSITA to apply it for other fungicidal uses, such as the agricultural methods taught by Kohn. Baker's teaching directly refuted the Patent Owner's prosecution argument that Austin was limited to "non-living materials" and was therefore non-analogous art.
  • Expectation of Success: Baker's confirmation of the compound's high potency in a living system, combined with Kohn's established teaching of applying similar compounds to plants, would have given a POSITA a very strong expectation of success.

• Additional Grounds: Petitioner asserted an additional obviousness challenge (Ground 3) based on the three-way combination of Austin, Kohn, and Sibley, which relied on the same core logic that the claimed compound was known to be a potent fungicide (from Austin) and that its application to plants was well-established (by Kohn and Sibley).

4. Key Claim Construction Positions

• Petitioner argued that the term "Controlling infestation" from independent claim 1 requires construction.
• Based on the prosecution history, where the applicant deleted the word "preventing" to overcome a §112 enablement rejection, Petitioner contended the term should be construed broadly. It was argued to encompass any amount of disease reduction relative to an untreated control, rather than requiring complete prevention. This construction was said to be consistent with the patent's examples, which report control levels between 50% and 80%, and is critical for mapping prior art that shows varying levels of fungicidal activity.

5. Key Technical Contentions (Beyond Claim Construction)

• A central contention was that the Patent Owner overcame the Examiner's rejections over Austin and Kohn using a scientifically flawed and misleading declaration (the Zeun declaration). Petitioner argued the declaration purported to show unexpected results but improperly failed to compare the claimed compound against the most relevant compound in Austin—"compound 66," which is identical to the claimed compound.
• Petitioner also contended that the Patent Owner's argument that Austin was non-analogous art (because it taught use on "non-living materials") was incorrect. Petitioner cited a Final Written Decision from a separate IPR against the Baker patent, where the Board rejected the same argument and found Austin to be reasonably pertinent to the problem of inhibiting microorganisms, regardless of the target.

6. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under 35 U.S.C. §325(d) would be inappropriate because the petition did not present the same art or arguments previously considered by the PTO.
• It was argued that three of the four grounds relied on new combinations of prior art the Examiner never considered. For the one combination the Examiner did review (Austin/Kohn), Petitioner contended that the allowance was based on a misunderstanding of the art caused by the Patent Owner's flawed expert declaration, warranting a new review.

7. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 1-12 of Patent 10,130,096 as unpatentable.