Nestlé PUrina PetCare Co v. Oil Dri Corp Of America

1. Case Identification

• Case #: IPR2015-00737
• Patent #: 5,975,019
• Filed: February 13, 2015
• Petitioner(s): Nestlé Purina Petcare Company
• Patent Owner(s): Oil-Dri Corporation of America
• Challenged Claims: 1-13, 30, and 32

2. Patent Overview

• Title: Clumping Animal Litter
• Brief Description: The ’019 patent discloses a clumping animal litter composition comprising a free-flowing blend of particulate non-swelling clay and particulate swelling clay. The invention is characterized by the mean particle size of the non-swelling clay being greater than the mean particle size of the swelling clay, which purportedly allows for effective clumping with less swelling clay than prior art compositions.

3. Grounds for Unpatentability

Ground 1: Claims 1-4, 6-13, 30, and 32 are anticipated under 35 U.S.C. §102 by Hughes.

• Prior Art Relied Upon: Hughes (Patent 5,386,803).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Hughes, which is directed to an "Animal Dross Absorbent," expressly discloses every element of the challenged claims. Independent claim 1 of the ’019 patent requires a clumping litter with (a) particulate non-swelling clay with a mean particle size no greater than 4 mm, (b) particulate swelling clay with a mean particle size no greater than 2 mm, wherein the mean particle size of the non-swelling clay is greater than that of the swelling clay. Petitioner contended Hughes discloses this directly:
    • Hughes teaches combining non-swelling calcium bentonite (smectite) with swelling sodium bentonite.
    • For limitation (a), Hughes discloses a preferred range for non-swelling clay of 600µ to 3350µ, which yields a calculated mean particle size of 1.975 mm (well below the 4 mm limit).
    • For limitation (b), Hughes discloses ranges for swelling clay of 50µ to 3350µ, yielding a mean particle size of 1.7 mm (below the 2 mm limit).
    • For the "wherein" clause, the calculated mean particle size of the non-swelling clay (1.975 mm) is greater than that of the swelling clay (1.7 mm).
  • Key Aspects: Petitioner asserted that Hughes also explicitly teaches the limitations of various dependent claims, including specific weight percentage ranges for both clay types (e.g., non-swelling clay at 60% by weight, anticipating claim 7) and particle size ratios (a calculated ratio of 1.16:1, anticipating claim 4). Furthermore, method claim 30 was alleged to be anticipated because combining, mixing, and packaging a litter composition were all inherent or expressly taught steps in Hughes.

Ground 2: Claims 1-4, 6-13, 30, and 32 are anticipated under §102 by Pattengill.

• Prior Art Relied Upon: Pattengill (Patent 5,458,091).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that Pattengill, titled "Clumpable Animal Litter Mixture," independently anticipates all challenged claims through its disclosure of specific tested compositions, particularly "Mixture No. 11." This mixture is a blend of a non-swelling clay product ("Tidy Cat") and a swelling clay product ("Scoop Fresh").
    • Pattengill's Mixture No. 11 discloses non-swelling clay particles with sizes between 0.6 mm and 2.36 mm and swelling clay particles with sizes between 0.6 mm and 1.18 mm.
    • Petitioner calculated a mean particle size for the non-swelling clay in this mixture of 1.52 mm (below the 4 mm limit of claim 1(a)).
    • Petitioner calculated a mean particle size for the swelling clay of 0.89 mm (below the 2 mm limit of claim 1(b)).
    • The calculated mean size of the non-swelling clay (1.52 mm) is greater than that of the swelling clay (0.89 mm), satisfying the "wherein" clause.
  • Key Aspects: Petitioner highlighted that Pattengill's Mixture No. 11 also anticipates dependent claims, such as containing 69.2% non-swelling clay (anticipating claims 6 and 7) and having a mean particle size ratio of 1.7:1 (anticipating claim 4). Critically, Mixture No. 11 also includes 1.2% "Plantago stabilizer," a known starch, which Petitioner argued anticipates claim 13’s requirement for an "organic clumping agent."

• Additional Grounds: Petitioner asserted that claims 1-13, 30, and 32 are obvious under §103 over Hughes, Pattengill, or the combination of Hughes and Pattengill. This ground argued that even if the references did not explicitly anticipate every limitation, a person of ordinary skill in the art would have found it obvious to select the claimed particle sizes, ratios, and compositions from the ranges disclosed in both references to arrive at the claimed invention.

4. Key Claim Construction Positions

• "Mean Particle Size": Petitioner proposed that under the broadest reasonable construction, this term means the average of the known particle sizes or sizes of groupings of particle sizes. This construction was central to Petitioner's anticipation arguments, as it allowed them to calculate a "mean" value from a disclosed range in the prior art (e.g., by averaging the upper and lower bounds) and map that value directly to the claim limitation.
• "Particulate Non-Swelling Clay" & "Particulate Swelling Clay": Petitioner argued these terms should be construed to mean separate, discrete, free-flowing particles of the respective clay types. This construction supports the argument that the prior art, which describes combining distinct clay particles, teaches the claimed invention, as opposed to a novel agglomerated mass.

5. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 1-13, 30, and 32 of the ’019 patent as unpatentable.