DCT
5:23-cv-02432
Columbia Insurance Co v. Simpson Strong Tie Co Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Columbia Insurance, Co. (Nebraska) and MiTek Inc. (Missouri)
- Defendant: Simpson Strong-Tie Company Inc. (California)
- Plaintiff’s Counsel: Practus, LLP and Stinson LLP
- Case Identification: 5:23-cv-02432, N.D. Cal., 05/17/2023
- Venue Allegations: Venue is alleged in the Northern District of California on the basis that Defendant is a California corporation with a principal place of business in the district, has committed acts of infringement in the district, and maintains a regular and established place of business there.
- Core Dispute: Plaintiffs allege that Defendant’s fire wall hangers infringe two patents related to structural connectors designed to attach floor joists or trusses to fire separation walls without compromising the wall's fire-resistant sheathing.
- Technical Context: The technology addresses a specific problem in multi-family and commercial construction, where building codes require maintaining the integrity of fire-rated walls, a challenge when structural members must be attached to them.
- Key Procedural History: The complaint details a significant history of disputes between the parties over this technology. A related patent, U.S. Patent No. 10,316,510, was the subject of prior litigation and a Post Grant Review (PGR) proceeding (PGR2019-00063) where its original claims were invalidated but a substitute claim was found patentable, a decision affirmed by the Federal Circuit. The '867 Patent-in-Suit, a continuation of the family, was also challenged by Defendant in a PGR (PGR2021-00109), where the Patent Trial and Appeal Board (PTAB) issued a Final Written Decision finding that Defendant failed to demonstrate the challenged claims were unpatentable. The '626 Patent is a further continuation in the same family.
Case Timeline
| Date | Event |
|---|---|
| 2013-12-31 | Priority Date for '867 and '626 Patents |
| 2014-07-01 | Plaintiff MiTek releases its FWH Hangers |
| 2017-06-01 | Defendant Simpson releases its Predecessor DG Hangers |
| 2019-04-01 | Defendant Simpson releases the Accused DGF/DGHF/DGBF Hangers |
| 2021-06-01 | U.S. Patent No. 11,021,867 ('867 Patent) issues |
| 2021-06-25 | Defendant is notified of infringement of the '867 Patent |
| 2021-08-13 | Defendant petitions for Post Grant Review of the '867 Patent |
| 2022-03-17 | PTAB institutes Post Grant Review of the '867 Patent |
| 2023-03-15 | PTAB Final Written Decision finds claims of '867 Patent not unpatentable |
| 2023-05-16 | U.S. Patent No. 11,649,626 ('626 Patent) issues |
| 2023-05-17 | Complaint filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 11,021,867 - "Hanger for Fire Separation Wall"
- Issued: June 1, 2021
The Invention Explained
- Problem Addressed: In construction requiring fire separation walls, traditional structural hangers necessitate cutting large openings in the fire-retardant sheathing (e.g., gypsum board) to attach joists to the wall frame. These cutouts create significant discontinuities, which can decrease the wall's resistance to fire. (’867 Patent, col. 1:24-42).
- The Patented Solution: The invention is a structural hanger with three main parts: a channel-shaped portion to receive the joist, a connection portion to attach to the wall frame, and a novel extension portion that connects the other two parts. This extension portion is designed to pass through a minimal slot in the sheathing, allowing the joist to be supported away from the wall while the hanger is secured to the frame behind the sheathing, thereby minimizing the disruption to the fire barrier. (’867 Patent, col. 2:4-23, Fig. 1).
- Technical Importance: This design allows for the installation of hangers either before or after sheathing is applied, increasing construction flexibility and maintaining the integrity of fire-rated wall assemblies. (Compl. ¶¶16-17).
Key Claims at a Glance
- The complaint asserts dependent claims 13 and 18, which incorporate independent claim 1. (Compl. ¶117).
- Essential elements of Independent Claim 1 include:
- A channel-shaped portion configured to receive a structural component, including a base lying in a base plane.
- A connection portion configured for wall attachment, including a back flange.
- The connection and channel-shaped portions being in a fixed, spaced apart relation.
- An extension portion with first and second extension flanges extending from the channel-shaped portion to the connection portion, configured to pass through sheathing.
- The extension flange planes being generally perpendicular to the base plane.
- The back flange and channel-shaped portion defining a sheath space sized to receive the sheathing, such that the channel portion is on one side of the sheathing and the back flange is on the other.
- The complaint reserves the right to assert other claims, including dependent claims. (Compl. ¶35).
U.S. Patent No. 11,649,626 - "Hanger for Fire Separation Wall"
- Issued: May 16, 2023
The Invention Explained
- Problem Addressed: The ’626 Patent addresses the same technical problem as the ’867 Patent: connecting structural components to fire-rated walls without compromising the fire barrier. (’626 Patent, col. 1:25-41).
- The Patented Solution: The solution is also a three-part hanger designed to pass through the sheathing. However, the claims of the ’626 Patent are more specific, explicitly reciting a hanger for a wall adapted to have "two layers of 5/8-inch-thick drywall mounted thereon" and an extension portion sized to receive that specific thickness. (’626 Patent, col. 12:5-18).
- Technical Importance: This patent specifies the invention's application to a common construction standard for achieving a two-hour fire rating, providing more targeted protection for this use case. (Compl. ¶13).
Key Claims at a Glance
- The complaint asserts independent claim 1. (Compl. ¶126).
- Essential elements of Independent Claim 1 include:
- A fire wall hanger for a frame wall adapted to have two layers of 5/8-inch-thick drywall.
- A channel-shaped portion to receive the structural component.
- A connection portion with a top flange (to engage the top of the wall plate) and a back flange (to engage the vertical face of the wall plate).
- An extension portion with a first extension flange, spacing the channel-shaped portion from the back flange by a distance sized large enough to permit the two layers of 5/8-inch-thick drywall to be received between them.
- The channel-shaped, extension, and connection portions being rigidly fixed with respect to one another.
III. The Accused Instrumentality
Product Identification
- Simpson Strong-Tie Fire Wall Hangers, models DGF, DGHF, and DGBF, and their skewed and offset versions (the "Infringing Products"). (Compl. ¶32).
Functionality and Market Context
- The Infringing Products are one-piece metal structural connectors designed to attach joists or trusses to wall framing. (Compl. ¶31). The complaint alleges they each possess a channel-shaped portion to hold a joist, a connection portion with top and back flanges to attach to the wall, and an extension portion connecting the two. (Compl. ¶¶38-40). The complaint includes an annotated image of the accused DGF product, which highlights in red the channel-shaped portion and in blue the top and back flanges of the connection portion. (Compl. p. 8). The Infringing Products are marketed as featuring "enough space for two layers of 5/8" gypsum board (drywall) to be slipped into place after the framing is complete." (Compl. ¶37, Ex. D).
- The complaint alleges that these products were released to the market to replace a predecessor line and to compete directly with Plaintiffs' patented FWH Hangers. (Compl. ¶¶55, 61).
IV. Analysis of Infringement Allegations
'867 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a channel-shaped portion configured to receive the structural component...the base having an upper surface...lying in a base plane | Each product has a channel-shaped portion with a base and side panels configured to receive a joist or truss. | ¶38 | col. 4:35-44 |
| a connection portion configured for attachment to the wall, the connection portion including a back flange having an upper edge | Each product has a connection portion with a top flange and a back flange for attachment to the top plate of a wall frame. | ¶39 | col. 4:62-67 |
| the connection portion and channel-shaped portion being in a fixed, spaced apart relation relative to one another | The products are constructed of metal with no moving parts, making the portions rigidly fixed in a spaced apart relation. | ¶45 | col. 12:29-32 |
| an extension portion including first and second extension flanges extending from the channel-shaped portion to the connection portion, each extension flange being configured to extend through the sheathing | Each product has first and second extension flanges that extend from the channel-shaped portion to the connection portion and are configured to pass through sheathing like drywall. | ¶¶40-41 | col. 5:1-6 |
| the extension flange planes being generally perpendicular to the base plane | Each product has at least one extension flange plane that is perpendicular to the plane defined by the upper surface of the base. An annotated diagram is provided to illustrate this geometric relationship. (Compl. p. 9). | ¶42 | col. 12:35-39 |
| the back flange and the channel-shaped portion defining a sheath space sized and shaped to receive the sheathing therein so that the channel-shaped portion is located on one side of the sheathing and the back flange is located on an opposite side... | The product's back flange and channel-shaped portion define a space, labeled a "drywall gap" in an annotated diagram, for receiving sheathing, positioning the channel on one side and the flange on the other. (Compl. p. 10). | ¶44 | col. 12:39-44 |
'626 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A fire wall hanger for connecting a structural component to a frame wall adapted to have two layers of 5/8-inch-thick drywall mounted thereon | The Infringing Products are marketed as hangers for walls adapted to have sheathing, specifically featuring enough space for two layers of 5/8" gypsum board. | ¶37 | col. 12:5-9 |
| a channel-shaped portion configured to receive the structural component | Each product has a channel-shaped portion configured to receive a joist or truss. | ¶38 | col. 12:10-11 |
| a connection portion including a top flange arranged to engage a top surface of a top plate of the frame wall and a back flange extending from an edge of the top flange | Each product has a connection portion with a top flange to overlie the top plate of a wall and a back flange extending from an edge of the top flange. | ¶39 | col. 12:12-16 |
| an extension portion...spacing the channel-shaped portion from the back flange plane by a distance sized large enough to permit the two layers of 5/8-inch-thick drywall...to be received between the channel-shaped portion and the back flange plane | The extension portion provides a space between the channel-shaped portion and the back flange plane, sized to receive two layers of 5/8" gypsum board, per Defendant's own marketing materials. | ¶¶43-44 | col. 12:17-22 |
| wherein the channel-shaped portion, the extension portion and the connection portion are rigidly fixed with respect to one another | The products are constructed of metal and have no moving parts, making the portions rigidly fixed relative to one another. | ¶45 | col. 12:23-25 |
Identified Points of Contention
- Scope Questions: A central question for the ’626 Patent will be whether the accused products, as sold, are "adapted to have two layers of 5/8-inch-thick drywall mounted thereon." The complaint relies on Defendant's marketing materials to support this element, which raises the evidentiary question of whether the physical product itself meets the claim limitation or if infringement depends on a specific marketed use.
- Technical Questions: For the '867 Patent, a potential point of dispute may be the claim term "generally perpendicular." The complaint provides a diagram alleging this geometric relationship exists in the accused products (Compl. p. 9), but the exact scope of "generally" may be a subject of claim construction and factual analysis. The complaint alleges the portions of the accused products are in a "fixed, spaced apart relation" because they are single pieces of metal; a question for the court may be whether this construction satisfies the claim term as it was understood in the patent.
V. Key Claim Terms for Construction
The Term: "fixed, spaced apart relation" (’867 Patent, Claim 1) / "rigidly fixed" (’626 Patent, Claim 1)
Context and Importance: These terms are critical to defining the structural integrity of the hanger. The complaint alleges the unitary metal construction of the accused products meets these limitations. (Compl. ¶45). The extensive procedural history, including PTAB proceedings on a parent patent, suggests the meaning of "rigidly fixed" has been previously litigated, and practitioners may focus on whether the doctrine of issue preclusion applies to its construction here.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specifications do not appear to provide an explicit definition, which may suggest the terms should be given their plain and ordinary meaning to one of skill in the art, potentially covering any non-pivoting or non-articulating connection.
- Evidence for a Narrower Interpretation: The detailed descriptions consistently show embodiments formed from a single stamped and bent piece of metal. (e.g., ’867 Patent, Fig. 15). A defendant could argue this context limits the scope of "fixed" to a unitary construction, as opposed to, for example, a welded or bolted assembly.
The Term: "sheath space sized and shaped to receive the sheathing" (’867 Patent, Claim 1)
Context and Importance: This term defines the critical gap that allows the hanger to function as described without requiring large cutouts in the drywall. Infringement hinges on the accused products possessing a space that meets this functional and dimensional requirement.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent states the space is defined between "the back flange and the back wall [of the channel-shaped portion]," and that it is "sized to receive the sheathing." (’867 Patent, col. 2:61-64). This broad functional language could be argued to cover any space that can accommodate sheathing.
- Evidence for a Narrower Interpretation: The ’626 Patent, a continuation, explicitly quantifies this space as "sized large enough to permit the two layers of 5/8-inch-thick drywall." (’626 Patent, col. 12:19-21). A defendant might argue this subsequent specificity in a related patent suggests the term in the '867 Patent should be construed more broadly, or conversely, a plaintiff might argue it illuminates the intended meaning in the parent patent.
VI. Other Allegations
- Willful Infringement: The complaint alleges willful infringement of both patents. For the ’867 Patent, it alleges Defendant had knowledge as of a June 25, 2021 notification letter, and further alleges objective recklessness based on Defendant's continued sales after its own PGR challenge against the patent failed at the PTAB. (Compl. ¶¶83, 91, 119-122). For the ’626 Patent, it alleges knowledge as of at least the patent's issue date of May 16, 2023, and that any infringement after service of the complaint is willful. (Compl. ¶¶128-131).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of preclusion and prosecution history: given that the asserted claims of the ’867 Patent have already survived a PGR challenge brought by the same Defendant, a key question is what preclusive effect that PTAB decision will have on Defendant’s ability to raise invalidity defenses in this litigation.
- A key evidentiary question will be one of structural and functional correspondence: does the physical geometry of the accused hangers—specifically the dimensions of the "sheath space" and the angular relationship between the "extension flange planes" and the "base plane"—map onto the specific language of the asserted claims? The complaint's reliance on Defendant's own marketing materials will be central to proving the functional aspects of the claims.
- A central question for damages will be willfulness: can Plaintiffs establish that Defendant's continued infringement after receiving notice and, particularly for the '867 patent, after losing a PGR challenge, was objectively reckless and egregious, thereby justifying an award of enhanced damages?