PTAB

PGR2020-00028

Syngenta Crop Protection AG v. FMC Corp

Key Events

Petition

Title: Pyrrolidinones as Herbicides
Brief Description: The ’202 patent relates to a broad genus of pyrrolidinone compounds, compositions containing them, and methods of using them as herbicides for controlling the growth of undesired vegetation. The claims encompass potentially billions of distinct chemical compounds.

Prior Art Relied Upon: Not applicable.
Core Argument for this Ground:
- Prior Art Mapping: Petitioner argued that the patent fails to enable a person of ordinary skill in the art (POSA) to make and use the full scope of the claimed invention without undue experimentation. The specification claims a vast genus of compounds but provides biological test data for only approximately 350 examples and synthesis schemes for only seven. Petitioner asserted that herbicidal activity is highly unpredictable, and the limited data shows that minor structural changes, particularly at the Q¹, Q², R¹, and R⁶ substituent positions, can drastically reduce or eliminate efficacy.
- Expectation of Success: The petition contended that a POSA would have no reasonable expectation of success in predicting which of the billions of unclaimed but claimed compounds would be effective herbicides. Many tested compounds demonstrated no herbicidal activity even at high screening concentrations, indicating that the claimed utility is not a general feature of the entire genus. Furthermore, Petitioner argued the patent’s synthesis methods are not enabling for the full scope of claimed structures, such as those with N-linked heterocycles at the Q¹ position, which would require a POSA to develop new synthetic routes.

Prior Art Relied Upon: Olsson (Application # 2007/0123508).
Core Argument for this Ground:
- Prior Art Mapping: Petitioner asserted that Olsson, which discloses PAR2-modulating compounds, teaches every limitation of the challenged claims. The core chemical structure in Olsson—a 5-membered pyrrolidinone ring—is identical to that of the ’202 patent when certain disclosed options are selected. The petition provided a detailed mapping correlating the substituent positions in the ’202 patent (e.g., Q¹, Q², R¹, R⁶) to corresponding positions in Olsson (e.g., R₁, R₅b, R₂, R₅c). Olsson allegedly discloses the same classes of chemical groups for these positions as are required by the claims, including optionally substituted phenyls, heteroaromatic compounds, and other heterocyclic rings. Petitioner argued that by disclosing the core structure and each of the claimed substituent types, Olsson expressly describes compounds falling within the scope of independent claims 1 and 31, as well as the narrower dependent claims.

Prior Art Relied Upon: Olsson (Application # 2007/0123508).
Core Argument for this Ground:
- Prior Art Mapping: In the alternative to anticipation, Petitioner argued that Olsson renders the challenged claims obvious. Olsson discloses the same core molecular structure and a vast array of the same or similar substituent groups at corresponding positions. Any minor differences between the claimed compounds and Olsson’s specific examples would have been obvious variations of Olsson’s disclosed compounds.
- Motivation to Combine (Modify): A POSA would combine Olsson’s teachings to arrive at the claimed invention. Olsson explicitly stated there was strong interest in modifying its disclosed compounds because of their applicability to the PAR2 enzyme, which has wide physiological relevance. This provided a clear reason to explore variations of the disclosed chemical scaffold.
- Expectation of Success: A POSA would have had a reasonable expectation of success in making routine substitutions on the known pyrrolidinone core to produce compounds with similar or useful properties.
Additional Grounds: Petitioner asserted a separate ground that claims 9-13 are invalid for lack of written description under §112, arguing that the specification’s limited data fails to demonstrate the inventor was in possession of the full scope of the claimed herbicidal compositions and uses.

Petitioner argued that the "when" clauses present in claims 1 and 31 (e.g., "when Q² is a 1H-pyrazol-3-yl ring...") should be construed as conditional limitations, equivalent to "if." This construction means the limitation only applies if the specified condition is met and does not require the condition to be present in every embodiment of the claim.

A central technical contention is the high degree of unpredictability in the field of herbicide design. Petitioner argued that structure-activity relationships are not well understood, and small modifications to a chemical structure can lead to a total loss of herbicidal activity. This principle was used to argue that the patent's limited examples cannot support the broad claims, as a POSA could not reliably predict activity across the claimed genus, thus requiring undue experimentation.

Petitioner argued that discretionary denial under 35 U.S.C. §325(d) would be inappropriate. The petition asserted that its §112 grounds (enablement and written description) were never raised by the Examiner during prosecution. While Olsson was listed in an Information Disclosure Statement, it was never applied by the Examiner in any rejection, meaning the specific anticipation and obviousness arguments based on Olsson were not previously considered by the USPTO.

Petitioner requests the institution of a Post-Grant Review and the cancellation of claims 1-7, 9-13, and 21-31 of the ’202 patent as unpatentable.