PTAB

IPR2017-01351

New NGC Inc v. United States Gypsum Co

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Gypsum Board Compositions with Enhanced Sag Resistance
  • Brief Description: The ’980 patent discloses gypsum-containing building products, particularly gypsum boards, formed from a composition of set gypsum, water, and sodium trimetaphosphate (STMP). The patent asserts that the inclusion of STMP as an "enhancing material" in specific concentrations results in a final product with improved sag resistance.

3. Grounds for Unpatentability

Ground 1: Obviousness of Claims 1-2 and 4-7 over Graux, Hjelmeland, ASTM C473-95, Sucech, and Summerfield

  • Prior Art Relied Upon: Graux (Patent 5,932,001), Hjelmeland (Patent 5,980,628), ASTM C473-95, Sucech (Patent 5,643,510), and Summerfield (Patent 2,985,219).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the prior art collectively disclosed every element of the challenged claims. Graux taught a plaster composition containing the core ingredients: calcined gypsum, water, and STMP (used as a crosslinker for starch). To meet the claimed concentration ranges, Petitioner pointed to Hjelmeland, which disclosed adding a polyphosphate (understood by a POSITA to include STMP) in amounts that Petitioner’s expert calculated to overlap with the claimed ranges of 0.004-2.0% (claim 1) and 0.04-0.16% (claim 2). The sag resistance limitation of claim 4 was addressed by combining Graux with ASTM C473-95, the industry-standard test for measuring sag that the ’980 patent itself identifies. Petitioner contended that adding STMP was known to improve sag, and measuring this inherent property via a standard test was obvious. For dependent claims, Petitioner asserted that Sucech taught adding foaming agents (claim 6) and Summerfield taught sandwiching a gypsum core between paper cover sheets (claim 7), both of which were conventional manufacturing steps.
    • Motivation to Combine: Petitioner argued a POSITA would combine these references to solve the well-known problem of sag in gypsum products. A POSITA starting with the basic composition from Graux would be motivated to optimize the STMP concentration for performance by consulting a reference like Hjelmeland, which taught specific ranges for polyphosphates. Since improving sag resistance was a known goal, a POSITA would naturally use the standard ASTM test to quantify the results. To produce a modern, commercially relevant board, a POSITA would have found it obvious to incorporate the standard techniques of adding foam for weight reduction (from Sucech) and using paper facers (from Summerfield).
    • Expectation of Success: Petitioner asserted a high expectation of success because all references operate in the same technical field of gypsum products and address known problems with predictable solutions. The outcome of combining an enhancing material (STMP) with standard manufacturing techniques would have been reasonably predictable.

Ground 2: Obviousness of Claims 1-2 and 4-7 over Satterthwaite, Hjelmeland, ASTM C473-95, Sucech, and Summerfield

  • Prior Art Relied Upon: Satterthwaite (Patent 3,234,037), Hjelmeland (Patent 5,980,628), ASTM C473-95, Sucech (Patent 5,643,510), and Summerfield (Patent 2,985,219).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground presented a similar argument to Ground 1 but substituted Satterthwaite as the primary reference. Petitioner argued Satterthwaite was even more direct, as it disclosed a set gypsum product (acoustical tile) made from water, gypsum, and a starch treated with STMP for the explicit purpose of achieving "increased resistance to warp or sag." The roles of the secondary references remained identical to Ground 1: Hjelmeland supplied the overlapping concentration ranges for STMP, ASTM C473-95 provided the standard method for testing sag, Sucech taught the use of foaming agents, and Summerfield taught the paper-faced board structure.
    • Motivation to Combine: The motivation to combine was argued to be exceptionally strong. A POSITA seeking to improve sag resistance would be directly led to Satterthwaite, which expressly taught using STMP for that exact purpose. Petitioner contended that a POSITA would readily apply the teachings from Satterthwaite's acoustical tiles to the closely related product of gypsum board. The motivation to incorporate Hjelmeland for dosage optimization, ASTM for testing, and Sucech and Summerfield for standard manufacturing processes followed the same compelling logic as in Ground 1.
    • Expectation of Success: Petitioner claimed a very high expectation of success. Satterthwaite explicitly connected the use of STMP to the desired outcome of improved sag resistance, making the result of the combination not just predictable but expressly taught by the primary reference.

4. Key Claim Construction Positions

  • Petitioner argued that the term "set gypsum" should be construed broadly according to its definition in the ’980 patent specification. The proposed construction was "any product containing calcium sulfate dehydrate," which would include not only gypsum boards but also plasters, acoustical tiles, and other related materials. This construction was central to Petitioner's arguments, as it justified applying prior art like Graux (disclosing plaster) and Satterthwaite (disclosing acoustical tiles) to the challenged claims directed to a "gypsum board."

5. Relief Requested

  • Petitioner requests institution of an inter partes review and cancellation of claims 1-2 and 4-7 of Patent 7,758,980 as unpatentable.