CertainTeed LLC v. Stone Creek Products LLC

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: CertainTeed LLC (Delaware)
  • Defendant: STONE CREEK PRODUCTS, LLC, d/b/a AFFINITY STONE (Illinois)
  • Plaintiff's Counsel: Latham & Watkins LLP; Heyl, Royster, Voelker & Allen, P.C.
• Case Identification: CERTAINTEED LLC v. STONE CREEK PRODUCTS, LLC, 2:26-cv-02083, C.D. Ill., 03/16/2026
• Venue Allegations: Venue is asserted on the basis that Defendant is an Illinois limited liability company with a regular and established place of business in the district, where it has allegedly committed acts of infringement.
• Core Dispute: Plaintiff alleges that Defendant's manufactured stone veneer panels infringe three U.S. patents related to building panels featuring integrated inserts for improved moisture management and ease of installation.
• Technical Context: The technology at issue resides in the building materials industry, specifically focusing on manufactured siding panels that seek to replicate the aesthetics of natural stone while improving performance and reducing the cost and complexity of installation.
• Key Procedural History: The complaint alleges that Plaintiff has marked the packaging of its own commercial products (STONEfaçade® panels) with the asserted patent numbers since at least April 11, 2024, which may be relevant to allegations of willful infringement and claims for enhanced damages.

Case Timeline

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 9,169,652 - "System, Method and Apparatus for Manufactured Building Panel"

• Patent Identification: U.S. Patent No. 9,169,652, issued on October 27, 2015 (the "'652 Patent").

The Invention Explained

• Problem Addressed: The complaint describes prior art siding panels as facing technical challenges including moisture becoming trapped between the panel and the mounting wall, leading to potential mold and material deterioration Compl. ¶9 Additionally, traditional installation methods were often labor-intensive, and prior attempts to simplify the process struggled to achieve a secure and durable attachment Compl. ¶¶9-10
• The Patented Solution: The invention is a manufactured building panel containing an embedded insert Compl. ¶16 '652 Patent, abstract This insert includes an interior portion for structural reinforcement and an exterior portion with features designed to solve the prior art problems Compl. ¶16 Specifically, "stand-offs" protrude from the back of the panel to create a consistent air gap, or "rainscreen," for moisture drainage, while a "fastener hem" provides a dedicated strip for simple and secure attachment to a wall using fasteners like screws '652 Patent, col. 4:26-53 Compl. ¶10
• Technical Importance: This design aims to combine the aesthetic of traditional siding with the performance benefits of modern building science, namely improved moisture management and a simplified installation process that reduces the need for specialized labor Compl. ¶11

Key Claims at a Glance

• The complaint asserts independent claim 1 Compl. ¶43
• The essential elements of claim 1 include:
  • A panel body with front, back, top, bottom, and side walls.
  • An insert with a planar interior portion "embedded completely" within the body's interior volume.
  • An exterior portion of the insert that extends to the exterior of the body and includes a "fastener hem" and a "plurality of stand-offs."
  • The back of the fastener hem and the backs of the stand-offs define a "co-planar surface."
  • A structural arrangement where at least some stand-offs are connected inside the body, while at least some are "independent and detached" on the exterior.
  • A configuration where the fastener hem and stand-offs directly contact a mounting wall to provide a "rainscreen."

U.S. Patent No. 11,047,134 - "Manufactured Building Panel"

• Patent Identification: U.S. Patent No. 11,047,134, issued on June 29, 2021 (the "'134 Patent").

The Invention Explained

• Problem Addressed: The '134 Patent, sharing a specification with the '652 Patent, addresses the same problems of moisture management and complex installation in manufactured siding panels '134 Patent, col. 1:36-43
• The Patented Solution: Like the '652 Patent, the '134 Patent describes a panel with an embedded insert that provides both stand-offs for a rainscreen and a fastener hem for attachment '134 Patent, abstract This patent's claims introduce the concept of a "positioning stop" on the insert, which is described in the specification as a feature used to properly center and position the insert within the mold during the panel's manufacturing process '134 Patent, col. 5:51-64 '134 Patent, col. 6:1-4
• Technical Importance: The addition of features like the positioning stop points to innovations in the manufacturing process itself, aiming to ensure consistency and proper alignment of the functional components within the panel during fabrication '134 Patent, col. 6:62-65

Key Claims at a Glance

• The complaint asserts independent claim 1 Compl. ¶62
• The essential elements of claim 1 include:
  • A panel body.
  • An insert with an interior portion embedded within the body.
  • The insert features "at least one standoff" protruding from the back of the body.
  • The insert also has an exterior portion with a "fastener hem" and "at least one positioning stop" coupled to the interior portion.
  • The back of the standoff(s) and the back of the fastener hem are "substantially coplanar."

U.S. Patent No. 11,828,071 - "Manufactured Building Panel Assembly"

• Patent Identification: U.S. Patent No. 11,828,071, issued November 28, 2023 (the "'071 Patent") Compl. ¶24
• Technology Synopsis: The '071 Patent claims an assembly of multiple building panels, rather than a single panel Compl. ¶26 It focuses on the interaction between a first and second panel, where the standoffs of both panels are "substantially coplanar" and configured to work together to provide a continuous rainscreen for the overall panel assembly '071 Patent, claim 1 The claims also require features like a fastener hem with apertures on the first panel '071 Patent, claim 1
• Asserted Claims: The complaint asserts independent claim 1 Compl. ¶75
• Accused Features: The complaint alleges that the installation and assembly of multiple Accused Products together create an infringing system Compl. ¶¶76-78 This includes allegations that the standoffs on adjacent accused panels align to form a coplanar surface and create a unified rainscreen for the assembly Compl. ¶78

III. The Accused Instrumentality

Product Identification

• The "Accused Products" are identified as Affinity Stone's "Cliff Ledge Series" and "Ridge Cut Series" mortarless stone veneer panels Compl. ¶32

Functionality and Market Context

• The complaint alleges the Accused Products are manufactured stone veneer panels that compete directly with Plaintiff's STONEfaçade® panels Compl. ¶31 The relevant technical features, as alleged in the complaint, include an "integrated air gap behind the panels" to prevent moisture trapping, an internal insert that connects stand-offs, a "[f]astening [s]trip" for installation with screws, and a "precision-engineered tongue and groove system" for interlocking panels Compl. ¶34 Compl. ¶35 Compl. ¶36 Compl. ¶37 The complaint includes an annotated photograph of a representative panel showing its front and back walls Compl. p. 8

IV. Analysis of Infringement Allegations

'652 Patent Infringement Allegations

• Identified Points of Contention:
  • Scope Questions: A potential issue may be the construction of "embedded completely." The defense may argue that the accused insert's "planar interior portion" is not "completely" within the panel body if any part of it is exposed or integral with the exterior portions in a way that differs from the patent's disclosure.
  • Technical Questions: The dual requirement for stand-offs to be both "connected directly to each other inside" and "independent and detached... on the exterior" may be a point of dispute. The analysis could turn on the specific physical structure of the accused insert and whether it meets both of these structural limitations simultaneously.

'134 Patent Infringement Allegations

• Identified Points of Contention:
  • Scope Questions: The term "positioning stop" may become a central issue. The '134 patent specification describes this feature in the context of positioning the insert within a mold during manufacturing '134 Patent, col. 5:51-64 A key question for the court may be whether a feature on the final, sold product can be construed as a "positioning stop" if its primary described function relates to the manufacturing process, not the product's end-use.
  • Technical Questions: The complaint appears to identify the same physical structure as both the "fastener hem" and the "positioning stop" Compl. p. 16 The defense may argue that these are distinct elements in the patent and that a single structure in the accused product cannot satisfy both limitations.

V. Key Claim Terms for Construction

For the '652 Patent

• The Term: "embedded completely"
• Context and Importance: This term is critical for defining the relationship between the insert's "planar interior portion" and the panel body. Infringement may depend on whether the accused insert's interior structure is entirely encased by the panel's material, or if some degree of exposure is permissible.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: The patent uses the term without providing a special definition, which may suggest it should be given its plain and ordinary meaning. A party might argue this allows for incidental or de minimis exposure of the interior portion that does not detract from its function.
  • Evidence for a Narrower Interpretation: Figure 9 of the patent shows a cross-section where the interior portion (43) of the insert (41) is fully surrounded by the material of the body (23), with no part of it reaching the surface '652 Patent, Fig. 9 This depiction could be used to argue that "completely" means fully and totally encased, without any exposure.

For the '134 Patent

• The Term: "positioning stop"
• Context and Importance: This term appears to be a key addition distinguishing the '134 patent's claims from the earlier '652 patent. Because the complaint's allegations for this element are less detailed than for others, its construction will be pivotal to the infringement analysis.
• Intrinsic Evidence for Interpretation:
  • Evidence for a Broader Interpretation: A party could argue that any structure on the insert that is "coupled to the interior portion" and serves to position the panel relative to another object (even another panel during installation) meets the limitation, broadening its scope beyond just the manufacturing context.
  • Evidence for a Narrower Interpretation: The detailed description states that positioning stops 85 are "configured for use, for example, only during formation of the body" and may be "disregarded" after molding '134 Patent, col. 5:51-57 This language strongly suggests the term refers to a manufacturing aid, not a feature of the final product intended for end-use, potentially narrowing the claim scope significantly.

VI. Other Allegations

• Indirect Infringement: The complaint alleges both induced and contributory infringement for all three patents. Inducement allegations are based on Defendant's publication and provision of "instructional manuals, brochures, and instructional videos" that allegedly guide customers to install and use the Accused Products in an infringing manner Compl. ¶53 Compl. ¶67 Compl. ¶80 Contributory infringement is alleged on the basis that Defendant sells components "knowing that such components are especially made or adapted for use in an infringement" and are not suitable for substantial non-infringing use Compl. ¶55 Compl. ¶69 Compl. ¶82
• Willful Infringement: Willfulness is alleged for all three patents based on Defendant's purported awareness of the patents since "at least as early as April 11, 2024." This alleged knowledge stems from Plaintiff's marking of its competing STONEfaçade® panel packaging with the patent numbers, constituting constructive notice Compl. ¶59 Compl. ¶72 Compl. ¶86 The complaint also asserts knowledge no later than the filing of the suit Compl. ¶59 Compl. ¶72 Compl. ¶86

VII. Analyst's Conclusion: Key Questions for the Case

• A core issue will be one of definitional scope: can the term "positioning stop," which the '134 Patent specification primarily describes as a manufacturing aid for positioning an insert within a mold, be construed to read on a structural feature of the final, sold product? The outcome of this claim construction dispute may be dispositive for the allegations concerning the '134 Patent.
• A second key question will be one of structural identity: does the accused panel's internal insert possess the specific, dual characteristics required by Claim 1 of the '652 Patent-namely, stand-offs that are simultaneously "connected" inside the panel body and "independent and detached" on the panel's exterior? The case may require a detailed factual analysis of the accused product's physical construction to determine if it meets this nuanced limitation.
• Finally, an evidentiary question will center on knowledge and intent: what evidence, beyond the allegation of constructive notice via patent marking, can Plaintiff provide to establish that Defendant had the requisite knowledge of the patents and specific intent to infringe, particularly for the pre-suit period relevant to willful infringement?