Simpson Strong Tie Co Inc v. Columbia Insurance Co

1. Case Identification

• Case #: PGR2021-00109
• Patent #: 11,021,867
• Filed: August 13, 2021
• Petitioner(s): Simpson Strong-Tie Company Inc.
• Patent Owner(s): Columbia Insurance Company
• Challenged Claims: 1-23

2. Patent Overview

• Title: Joist Hanger
• Brief Description: The ’867 patent discloses a joist hanger for connecting a structural component, like a joist, to a wall with sheathing. The hanger comprises a channel-shaped portion to receive the joist, a connection portion for attachment to the wall, and an extension portion that interconnects the other two portions, creating a fixed, spaced-apart relation that defines a "sheath space" for the sheathing.

3. Grounds for Unpatentability

Ground 1: Obviousness over Gilb in view of Bundy - Claims 1-12, 15-17, and 21-23 are obvious over Gilb in view of Bundy

• Prior Art Relied Upon: Gilb (Patent 4,422,792) and Bundy (Patent 9,394,680).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Gilb disclosed all structural elements of the claimed hanger, including a channel-shaped portion (stirrup members), a connection portion (base 36), and an extension portion (gusset members) that hold the other portions in a fixed, spaced-apart relation. Gilb, however, did not explicitly teach sizing this space to receive sheathing. Bundy, an analogous construction hanger patent, was argued to remedy this by teaching a hanger with an extension portion specifically sized to receive two layers of 5/8" thick sheathing between the channel-shaped portion and the wall.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine these references because they are from the same field of construction support hangers. It would have been obvious to apply the known technique from Bundy—sizing the hanger's spacing to accommodate sheathing for wall integrity—to the similar hanger structure in Gilb to achieve the predictable result of protecting a building's structural members.
  • Expectation of Success: A POSITA would have had an expectation of success because both Gilb's and Bundy's hangers are made of similar materials (metal) and are used for the similar purpose of connecting a structural component to a wall.

Ground 2: Anticipation and Obviousness over Timony and Bundy - Claims 1-4, 6, 10, and 11 are anticipated by Timony; Claims 5, 7-9, 12, 15-17, and 21-23 are obvious over Timony in view of Bundy

• Prior Art Relied Upon: Timony (Application # 2005/0155307) and Bundy (Patent 9,394,680).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Timony, which discloses a retrofit hanger, anticipated the core invention by teaching all elements of independent claim 1. Timony's hanger includes a channel-shaped portion (support 265), a connection portion (retaining portion 203), and an extension portion (retrofit plates 230) that maintain a fixed, spaced-apart relation, defining a space to receive sheathing (foam panels). For claims not fully disclosed by Timony, Petitioner argued Bundy’s teachings would have rendered them obvious. Bundy taught using fire-resistant sheathing and incorporating a stop to engage the end of the structural component.
  • Motivation to Combine: A POSITA would have been motivated to modify Timony's hanger based on Bundy's teachings as a matter of simple substitution. It would have been obvious to replace Timony's foam panels with Bundy's fire-resistant sheathing and to size the sheath space accordingly to improve wall integrity. Furthermore, incorporating Bundy's stop feature into Timony's design was presented as a known technique to achieve the predictable result of providing end support for the structural element.
  • Expectation of Success: A POSITA would have expected success in the combination because both references disclose metal hangers for similar construction purposes, and Timony explicitly states its hanger is suitable for use with framed partition walls like those in Bundy.

Ground 3: Obviousness over Tsukamoto in view of Bundy - Claims 1-12, 15-17, and 21-23 are obvious over Tsukamoto in view of Bundy

• Prior Art Relied Upon: Tsukamoto (Japanese Application No. 19991014482) and Bundy (Patent 9,394,680).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that Tsukamoto disclosed every structural component of the claimed hanger, including a channel-shaped portion (holding plates), a connection portion (vertical plates), and an extension portion (inclined portions) that create a fixed space between the other two portions. As with Gilb, the petition contended that Tsukamoto does not explicitly disclose sizing this space for sheathing. Bundy’s teaching of a hanger specifically sized to accommodate two layers of sheathing was argued to supply this missing element.
  • Motivation to Combine: A POSITA would combine the references to optimize a known device. It would have been obvious to take the existing space in Tsukamoto’s hanger and size it according to Bundy’s teachings to accommodate standard sheathing, thereby achieving the predictable benefit of protecting the wall structure.
  • Expectation of Success: A POSITA would have had an expectation of success because both hangers are used for similar purposes (hanging a structural object on a wall), and Tsukamoto’s design is compatible with the wood frame/drywall setting disclosed in Bundy.

• Additional Grounds: Petitioner also asserted that all claims are invalid under 35 U.S.C. §112 for indefiniteness and that claims 5 and 17 lack written description.

4. Key Claim Construction Positions

• "Planar": Petitioner argued that because the hanger is made of sheet metal with thickness, a 3D object cannot be "planar." Therefore, a POSITA would interpret "planar" in claim 2 as requiring that a surface of the extension flange is coincident with a plane, not the entire flange itself.
• "Fixed": While the claims use the term "fixed," Petitioner applied the Board's construction of "rigidly fixed" from a prior review of a related patent ("the ’510 patent"). This construction means "components are connected such that they do not move freely with respect to each other."

5. Key Technical Contentions (Beyond Claim Construction)

• Indefiniteness of "extension flange plane": Petitioner’s central technical contention was that the limitation "each extension flange lying in an extension flange plane" (claims 1-15) is indefinite. It argued that because the claim defines the location of the imaginary plane based on the three-dimensional, multi-planar extension flange itself—without specifying a particular surface—there are an infinite number of possible planes, rendering the claim scope uncertain.
• Indefiniteness of Functional Claiming: Petitioner argued claims 5 and 17 are indefinite because the functional language "maintaining a 2 hour fire resistance rating of the sheathing" fails to inform a POSITA of the required hanger structure, as the fire rating depends on the entire wall assembly (e.g., insulation, gypsum type), not just the hanger.

6. Arguments Regarding Discretionary Denial

• Petitioner argued that the Board should not exercise its discretion to deny institution under 35 U.S.C. §325(d). It contended that the asserted prior art combinations are materially different from those considered during prosecution. Specifically, Tsukamoto was never considered by the Examiner, and the primary references of Gilb’792 and Timony are materially different from the primary reference (Gilb’155) applied by the Examiner, as they disclose the "fixed, spaced-apart" feature the Examiner found lacking in Gilb'155. Petitioner asserted the Examiner erred by not substantially considering the relevance of this art.

7. Relief Requested

• Petitioner requested institution of a Post-Grant Review and cancellation of claims 1-23 of Patent 11,021,867 as unpatentable.