MonSanto Co v. Pioneer Hi BRed Intl Inc

1. Case Identification

• Case #: Unassigned
• Patent #: 5,518,989
• Filed: October 17, 2012
• Petitioner(s): Monsanto Company
• Patent Owner(s): Pioneer Hi-Bred International
• Challenged Claims: 1-7

2. Patent Overview

• Title: Seed Vigor by Pre-Harvest Defoliation of Maize Plants
• Brief Description: The ’989 patent discloses a method for enhancing the seed vigor of maize plants. The method involves reducing the functional leaf area of the plants (defoliation) within a specific timeframe—between about 600 and about 850 growing-degree days (GDDs) after pollination—before harvesting the seeds.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1 and 2 by Hunter

• Prior Art Relied Upon: Hunter (a June 1989 doctoral dissertation from the University of Kentucky).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Hunter disclosed every element of claims 1 and 2. Hunter described experiments involving the mechanical defoliation of maize plants to determine the effect on seed maturity and vigor. Petitioner calculated that the defoliation timing disclosed in Hunter—20 and 21 days after pollination (DAP)—corresponded to approximately 515-579 GDDs. Petitioner contended that due to the inherent imprecision of GDD calculations and the patent’s use of the term "about," this range fell within the claimed range of "between about 600 and about 850 GDDs." Hunter also explicitly taught that this defoliation treatment resulted in enhanced seed vigor, as measured by cold emergence tests, relative to undefoliated control plants.
  • Key Aspects: The core of this argument relied on construing the claimed GDD range broadly enough to encompass the slightly lower GDD values calculated from Hunter's disclosure.

Ground 2: Anticipation of Claims 1 and 2 by Vasilas

• Prior Art Relied Upon: Vasilas (a 1986 article in J. Seed Tech.) and Vasilas ’85 (a 1985 article in Agronomy J.).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Vasilas, when read with data from Vasilas ’85 detailing the same experiments, anticipated claims 1 and 2. Vasilas disclosed mechanically defoliating corn inbreds by hand and measuring the effect on seed quality via cold germination tests. While Vasilas did not provide pollination dates, Vasilas ’85 did. Using this data, Petitioner calculated that the defoliation occurred at approximately 786 GDDs (capped formula) or 860 GDDs (uncapped formula) after pollination. These values fell squarely within or at the endpoint of the claimed range. Vasilas explicitly reported that cold germination results were higher for the defoliated plants, directly teaching the claimed enhanced seed vigor.

Ground 3: Obviousness of Claims 1-5 over Hunter in view of Alcantara

• Prior Art Relied Upon: Hunter (a 1989 doctoral dissertation) and Alcantara (a 1988 article in Weed Tech.).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that even if Hunter did not anticipate the claims, it rendered them obvious, particularly when combined with Alcantara. Hunter taught enhancing seed vigor via mechanical defoliation at a GDD range very close to the claimed range. Alcantara taught chemical defoliation of corn using glyphosate (Roundup®) as a preharvest treatment, with defoliation timings calculated by Petitioner to be between 794 and 921 GDDs—a range that overlaps with and is close to the claimed range.
  • Motivation to Combine: A POSITA would combine these references because both addressed the same technical problem of managing maize plants pre-harvest to improve outcomes. Petitioner argued Alcantara’s chemical defoliation method using glyphosate was a well-known and predictable substitute for Hunter’s mechanical defoliation, as both were known methods for reducing leaf area to achieve similar agricultural goals.
  • Expectation of Success: A POSITA would have had a reasonable expectation of success in substituting Alcantara's chemical method for Hunter's mechanical method to achieve enhanced seed vigor. Since both references disclosed defoliation within or near the same GDD window, a POSITA would expect the resulting seeds to exhibit similar properties, namely the enhanced vigor taught by Hunter.

• Additional Grounds: Petitioner asserted numerous other grounds, including anticipation of claims 1 and 3-5 by Alcantara alone and by Major (a 1980 journal article) alone. Additional obviousness challenges were based on various combinations, such as Hunter in view of Hunter ’88 (a 1988 abstract); Vasilas in view of Vasilas ’85; Vasilas in view of Alcantara or Major; and Hunter in view of Major. Further grounds for claims 6-7 added the ’125 patent (Albrecht) to these combinations.

4. Key Claim Construction Positions

• Petitioner argued for a broad interpretation of the claim term "between about 600 and about 850 GDDs after pollination." This construction was central to nearly all grounds. Petitioner contended this range was imprecise for several reasons:
  • The use of the word "about" at both endpoints of the range.
  • The existence of two different, known methods for calculating GDDs (capped and uncapped), both referenced in the ’989 patent's prosecution history, which yield different results.
  • Inherent imprecision in determining the exact start time for GDD counting (i.e., the moment of pollination across an entire stand of plants) and the end time (the defoliation process can take several days).
• Based on these factors, Petitioner argued the broadest reasonable interpretation of the claimed range would encompass values well outside the literal 600-850 numbers, including values as low as 515 GDDs (from Hunter) and as high as 921 GDDs (from Alcantara).

5. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-7 of the ’989 patent as unpatentable.