1:15-cv-01067
N.D. Ill.Feb 22, 2019Background
- Oil-Dri owns U.S. Patent No. 5,975,019 for a "clumping animal litter" that relies on a synergy between relatively smaller swelling clay particles and relatively larger non‑swelling clay particles (predetermined mean particle sizes). Oil‑Dri sued Nestlé Purina for infringement.
- Nestlé Purina manufactures Tidy Cats litters using a wet process that produces composite granules (non‑swelling clay wet "seeds" coated with swelling clay dust and then dried). Parties dispute whether those composite granules satisfy the patent's "particulate" and "predetermined mean particle size" limitations.
- Procedurally: Nestlé Purina filed an IPR challenging validity (Board found claims not invalid; appeal/remand ongoing). District court conducted claim construction and considered cross‑motions for summary judgment by both parties.
- Disputed patent claims: independent claims 1 (product claim defined by ingredients with predetermined mean particle sizes) and 30 (method claim requiring a composition composed of separate and discrete particles). Dependent claims follow.
- The court previously construed key terms (e.g., "particulate" = separate and discrete particles; "predetermined" = decided upon in advance; "mean particle size" = average of a representative sample).
Issues
| Issue | Oil‑Dri's Argument | Nestlé Purina's Argument | Held |
|---|---|---|---|
| Whether claim 1 is read as describing the finished composition or the ingredients | Claim 1 covers the product by reference to its ingredients (so infringement can be assessed by inputs); Oil‑Dri argued ingredients-based reading | Nestlé Purina argued claim 1 limits protection to the finished litter (composition), excluding engineered composite granules | Court: Claim 1 is defined in terms of ingredients (ingredients reading), not limited to a final composition (Norian controlling) |
| Whether Nestlé Purina "predetermined" mean particle sizes (literal infringement of claim 1) | Oil‑Dri: Nestlé Purina predetermines sizes via supplier specifications and monitoring; thus meets claim 1 | Nestlé Purina: specs only give upper bounds; no proof of mean sizes decided in advance; experts dispute ability to calculate means; composite granules undermine particulate requirement | Court: Genuine factual dispute exists for jury; denied summary judgment to both sides on literal infringement of claim 1 (except Maricopa products) |
| Whether claim 30 (method) is infringed by Nestlé Purina's process/products | Oil‑Dri: asserted claim 30 is satisfied by Nestlé Purina process/inputs | Nestlé Purina: claim 30 requires a composition of separate and discrete particles after combining; composite granules are unified, not particulate | Court: Claim 30 requires particulate composition after combining; composite granules are not separate and discrete -> summary judgment for Nestlé Purina (no infringement of claim 30 and dependent claim 32) |
| Validity defenses: prior art, written description, equitable estoppel | Oil‑Dri: patent is valid; sought summary judgment against Nestlé Purina's invalidity defenses | Nestlé Purina: asserted anticipation/obviousness by (1) accused products predating the patent, (2) Western Aggregates' MoFoam, (3) Kitty Litter Maxx Scoop, (4) Shinohara; also argued lack of written description and equitable estoppel against enforcement | Court: Denied summary judgment to Oil‑Dri on prior‑art invalidity defenses (genuine issues for jury). Granted Oil‑Dri summary judgment on written description and equitable estoppel defenses (Nestlé Purina failed to raise triable facts on written description or misleading conduct for estoppel) |
Key Cases Cited
- Exxon Chem. Patents, Inc. v. Lubrizol Corp., 64 F.3d 1553 (Fed. Cir.) (composition language can limit claim scope to resultant product)
- PIN/NIP, Inc. v. Platte Chem. Co., 304 F.3d 1235 (Fed. Cir.) (treating "composition" claims as covering final product and guidance on infringement analysis)
- Mars, Inc. v. H.J. Heinz Co., L.P., 377 F.3d 1369 (Fed. Cir.) (construing "mixture"/composition language)
- Norian Corp. v. Stryker Corp., 432 F.3d 1356 (Fed. Cir.) (interpreting claim language referring to components "in terms of the components put into it")
- Akzo Nobel Coatings, Inc. v. Dow Chem. Co., 811 F.3d 1334 (Fed. Cir.) (literal infringement requires every claim limitation)
- Cybor Corp. v. FAS Techs., Inc., 138 F.3d 1448 (Fed. Cir.) (two‑step infringement analysis: claim construction then comparison)
- Teva Pharm. Indus. Ltd. v. AstraZeneca Pharm. LP, 661 F.3d 1378 (Fed. Cir.) (priority requires appreciation of what was made)
- Invitrogen Corp. v. Clontech Labs., Inc., 429 F.3d 1052 (Fed. Cir.) (date of conception tied to appreciation of invention)
- Mycogen Plant Sci. v. Monsanto Co., 243 F.3d 1316 (Fed. Cir.) (prior documentation need not recite claim language expressly to be prior art)
- Ariad Pharm., Inc. v. Eli Lilly & Co., 598 F.3d 1336 (Fed. Cir.) (written description requirement explained)
- Accent Packaging, Inc. v. Leggett & Platt, Inc., 707 F.3d 1318 (Fed. Cir.) (device altered after sale cannot be used to prove infringement)
- A.C. Aukerman Co. v. R.K. Chaides Const. Co., 960 F.2d 1020 (Fed. Cir.) (elements of equitable estoppel in patent context)