DCT
1:18-cv-00163
Sioux Chief Mfg Co Inc v. Zurn Industries LLC
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Sioux Chief Manufacturing Co., Inc. (Missouri)
- Defendant: Zurn Industries, LLC (Delaware) and Rexnord Corporation (Delaware)
- Plaintiff’s Counsel: Shook, Hardy & Bacon L.L.P.; Phillips Goldman McLaughlin & Hall, P.A.
- Case Identification: 1:18-cv-00163, D. Del., 01/29/2018
- Venue Allegations: Venue is alleged to be proper in the District of Delaware because both Defendants are incorporated in Delaware and are therefore considered to reside in the district.
- Core Dispute: Plaintiff alleges that Defendants’ floor drainage systems infringe a patent related to a system for installing drain fixtures in poured concrete slabs that allows for post-pour height adjustment.
- Technical Context: The technology concerns plumbing components used in commercial construction, specifically floor drains designed to be set in concrete, where proper final height and protection during the pour are critical.
- Key Procedural History: The complaint alleges a lengthy history between the parties, starting with a 2007 meeting where Zurn representatives allegedly examined Plaintiff's "FinishLine" products and inquired about patent protection. It further alleges that Zurn had knowledge of the asserted patent at least as early as September 2014, when a patent application assigned to Zurn cited it in an Information Disclosure Statement. Plaintiff sent a formal notice of infringement letter, including a claim chart for Claim 1, in October 2017.
Case Timeline
| Date | Event |
|---|---|
| 2005-08-12 | ’906 Patent Priority Date |
| 2006-01-01 | Plaintiff's "FinishLine" product line introduced |
| 2007-09-01 | Sioux Chief and Zurn representatives meet to discuss FinishLine products |
| 2013-01-08 | U.S. Patent No. 8,347,906 issues |
| 2014-09-05 | Zurn allegedly becomes aware of ’906 Patent via an IDS citation |
| 2017-08-01 | Defendants begin selling the Accused Products |
| 2017-10-25 | Sioux Chief sends notice letter to Zurn alleging infringement |
| 2017-11-24 | Sioux Chief sends follow-up letter to Zurn offering a license |
| 2018-01-29 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,347,906 - "Floor Drain Installation System"
- Issued: January 8, 2013
The Invention Explained
- Problem Addressed: The patent describes several long-standing problems in installing floor drains in concrete. These include the difficulty of adjusting the drain's height after the concrete has been poured, the need to protect the drain opening from being clogged with concrete or debris during the pour, and the risk of damage to the drain fixture from heavy construction equipment. (’906 Patent, col. 1:41-col. 2:22).
- The Patented Solution: The invention is a multi-part system that uses a removable "coring plug" or cap. This plug is installed in a "coring sleeve" before the concrete is poured. It serves two functions: it seals the drain pipe to prevent debris from entering, and it creates a precisely shaped void in the concrete slab around the drain opening. After the concrete has set, the inexpensive plug is removed and discarded, and the final drain fixture can be installed into the void and easily adjusted to be perfectly flush with the finished floor surface. (’906 Patent, Abstract; col. 2:23-51).
- Technical Importance: This approach decouples the rough plumbing installation from the final finish work, allowing for greater flexibility and reducing the risk of costly rework or damage on construction sites. (’906 Patent, col. 2:15-22).
Key Claims at a Glance
- The complaint asserts independent claims 1 (a system) and 14 (a method). (Compl. ¶¶52, 55).
- Independent Claim 1 (System) requires:
- A "utility access fixture" with a head and a central mounting stem.
- A "coring sleeve" with a connectable lower portion and an upper "bowl" that can removably receive the utility access fixture.
- A "cover" that can be positioned over the bowl cavity and sit "generally flush" with the bowl's upper edge.
- Independent Claim 14 (Method) requires steps of:
- Connecting a coring sleeve to a conduit.
- Installing a utility access fixture into the sleeve by threading it.
- Securing a cover over the fixture.
- Pouring and finishing material (e.g., concrete) around the assembly.
- Allowing the material to harden.
- Removing the cover.
- Adjusting the height of the utility access fixture to be flush with the finished surface.
- The complaint does not explicitly reserve the right to assert dependent claims but requests judgment that Defendants infringed "one or more claims." (Compl. p. 35, ¶A).
III. The Accused Instrumentality
Product Identification
- The accused products are Defendants' "EZ1 Drainage Series" floor drainage systems. (Compl. ¶39).
Functionality and Market Context
- The complaint alleges the EZ1 products are "complete and ready to install" solutions for commercial construction projects. (Compl. ¶41). The functionality at issue includes features for "easy post-pour adjustment, tilt accessory package, and an integrated strainer." (Compl. ¶43). The complaint presents a diagram from Defendants' installation instructions showing a cross-section of the installed EZ1 product in a concrete slab. (Compl. p. 15, Fig. 10). This diagram depicts a system with a temporary cover that is removed after the concrete pour, allowing a final drain assembly to be threaded into a sleeve and adjusted to the final floor height.
IV. Analysis of Infringement Allegations
’906 Patent Infringement Allegations (Claim 1 - System)
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a) a utility access fixture having a fixture head projecting radially outward from a central fixture mounting stem, | The Accused Products are alleged to include a utility access fixture with a fixture head projecting from a central mounting stem. The complaint provides a diagram from Defendants' installation instructions showing this component. (Compl. p. 15, Fig. 10). | ¶54, p. 15 | col. 5:1-9 |
| b) a coring sleeve having a lower portion connectable in fluid communication with said conduit and a bowl projecting outward from said lower portion...sized to removably receive the utility access fixture therein... | The EZ1 system allegedly includes a "coring sleeve" with a lower portion that connects to the conduit and a bowl that receives the fixture. The complaint alleges the fixture is removably received via a threading mechanism. | ¶54, pp. 17-19 | col. 5:40-6:2 |
| c) a cover removably positionable to extend across said bowl cavity...such that an upper surface of said cover extends generally flush with an upper edge of said bowl. | The Accused Products allegedly include a removable cover that is placed over the assembly before the concrete pour. The complaint includes a diagram from Defendants' materials annotated with "No Gap" to allege the cover sits flush with the bowl's edge. (Compl. p. 21, Fig. 5). | ¶54, pp. 20-21 | col. 6:11-31 |
’906 Patent Infringement Allegations (Claim 14 - Method)
| Claim Element (from Independent Claim 14) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a) connecting a coring sleeve to the conduit... | Defendants' instructions allegedly direct users to connect the coring sleeve to the pipe. | ¶57, p. 25 | col. 8:1-12 |
| b) installing a utility access fixture in the coring sleeve by threading the externally threaded stem... | The complaint alleges Defendants' instructions direct users to install the fixture by threading its stem into the sleeve. The complaint provides a screenshot from a promotional video showing this threaded engagement. (Compl. p. 25, YouTube Screenshot). | ¶57, p. 26 | col. 8:41-44 |
| c) securing a cover over the utility access fixture... | Users are allegedly instructed to secure a cover over the fixture so that its upper surface is flush with the upper edge of the bowl. | ¶57, p. 27 | col. 8:13-20 |
| d) pouring the poured material around said conduit; | The instructions allegedly direct users to pour concrete around the assembly. A screenshot from an instructional video shows concrete being poured. (Compl. p. 30, YouTube Screenshot). | ¶57, p. 29 | col. 8:21-22 |
| e) finishing the poured material to a level generally flush with said upper surface of the cover... | The instructions allegedly direct users to finish the concrete slab flush with the top of the cover. | ¶57, p. 29 | col. 8:22-25 |
| f) allowing the poured material to harden; | The complaint alleges that the instructions to "break away [the] concrete" to remove the cover inherently require the step of first allowing the concrete to harden. | ¶57, p. 31 | col. 8:31-33 |
| g) removing the cover to provide access to the utility access fixture; and | The instructions are alleged to direct users to hit the cover with pliers to break it loose from the hardened concrete and then remove it. | ¶57, p. 32 | col. 8:33-40 |
| h) adjusting the height of the utility access fixture relative to the coring sleeve until an upper surface...extends generally flush with a finished surface. | The instructions allegedly direct users to turn the head assembly until the top of the strainer is flush with the finished floor. | ¶57, p. 34 | col. 8:45-51 |
- Identified Points of Contention:
- Scope Questions: Claim 1 recites a "cover," while the patent specification primarily describes a "coring plug or cap" with a specific structure, including a stem. (’906 Patent, col. 6:11-19). The infringement analysis may raise the question of whether the term "cover" should be construed broadly to include any temporary shield, or be limited to the more specific "plug" embodiment disclosed in the patent.
- Technical Questions: For method claim 14, infringement liability for Defendants depends on their "direction or control" over their customers (contractors) who perform the installation steps. (Compl. ¶55). A key question will be whether the provided installation manuals and videos constitute sufficient direction or control to attribute the contractors' actions to the Defendants for the purpose of direct infringement under a joint-infringement theory.
V. Key Claim Terms for Construction
The Term: "cover" (Claim 1)
Context and Importance: This term defines the temporary component that protects the drain and creates the void. Its construction is critical because a narrow definition focused on the patent's specific "plug" embodiment could create a non-infringement argument for an accused product that uses a structurally different type of cover.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The plain language of Claim 1 simply uses the broad term "cover," which is not explicitly defined. The complaint alleges infringement by a component that Defendants' materials also call a "cover." (Compl. p. 27).
- Evidence for a Narrower Interpretation: The patent's detailed description and figures consistently show a "coring plug or cap" that has a distinct head and a threaded stem (e.g., plug 20, stem 73). (’906 Patent, col. 6:11-19; Fig. 3). An argument could be made that the invention is limited to this "plug" structure, not just any flat "cover."
The Term: "generally flush" (Claims 1, 14)
Context and Importance: This term of degree describes the required final alignment of the cover (pre-pour) and the utility fixture (post-pour) with the surrounding surfaces. Practitioners may focus on this term because disputes over such terms are common, and proving the accused product achieves the required degree of "flushness" is essential to Plaintiff's case.
Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The word "generally" itself suggests some tolerance for minor deviation, which is practical in the context of concrete finishing.
- Evidence for a Narrower Interpretation: The specification states that concrete is "finished to be coplanar with the upper surface 76 of the plug 20," suggesting a precise relationship. (’906 Patent, col. 8:22-24). The complaint reinforces a narrow interpretation by using a diagram from Defendants' materials annotated with the words "No Gap" to describe the fit of the cover. (Compl. p. 21).
VI. Other Allegations
- Indirect Infringement: The complaint alleges that Defendants direct and control their customers' installation of the accused products by disseminating "user guides/and or instruction manuals that provide... step-by-step guidance." (Compl. ¶44). These allegations form the basis for holding Defendants liable for direct infringement of method claim 14 under a joint infringement theory, and could also support a claim for induced infringement.
- Willful Infringement: The complaint alleges willfulness based on both pre- and post-suit knowledge. Pre-suit knowledge is alleged to stem from a 2007 meeting where Zurn examined Plaintiff's related products and discussed patents (Compl. ¶¶34-37), as well as a September 2014 Information Disclosure Statement where a Zurn-assigned patent application cited the ’906 Patent (Compl. ¶47). Post-suit knowledge is based on a detailed notice letter sent in October 2017. (Compl. ¶45).
VII. Analyst’s Conclusion: Key Questions for the Case
- A central issue will be one of claim scope: can the term "cover," as used in Claim 1, be interpreted broadly to read on the accused component, or will it be narrowed by the specification's disclosure of a more complex "coring plug" with a stem, potentially allowing Defendants to argue a design-around?
- A key legal question will be one of divided infringement: will the Plaintiff be able to prove that Defendants' installation instructions and marketing materials establish the high degree of "direction or control" over third-party contractors required by current case law to hold Defendants liable for direct infringement of the asserted method claim?
- A significant question for damages will be willfulness: do the allegations of a 2007 product meeting and a 2014 patent citation constitute the kind of pre-suit knowledge of infringement that a court would find to be "egregious" and thus sufficient to support a finding of willful infringement and enhanced damages?