DCT
5:23-cv-13236
NIBCO Inc v. Brasscraft Mfg Co
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: NIBCO Inc. (Indiana)
- Defendant: Brass-Craft Mfg Co (Michigan)
- Plaintiff’s Counsel: PRICE HENEVELD LLP
- Case Identification: 2:23-cv-13236, E.D. Mich., 12/20/2023
- Venue Allegations: Venue is asserted on the basis that Defendant BrassCraft resides in the Eastern District of Michigan.
- Core Dispute: Plaintiff alleges that Defendant’s tankless water heater valve assemblies and installation kits infringe six patents related to fluid isolation valve systems.
- Technical Context: The technology concerns multi-port valve assemblies that facilitate the installation, operation, and servicing of in-line appliances, such as tankless water heaters, by integrating flow control, isolation, and draining functions into compact units.
- Key Procedural History: Plaintiff NIBCO acquired the patents-in-suit from Webstone Co., Inc. on April 29, 2016. The complaint alleges that products made under the patents have been marked in compliance with 35 U.S.C. § 287.
Case Timeline
| Date | Event |
|---|---|
| 2001-06-22 | Earliest Priority Date for ’596 Patent |
| 2003-09-23 | Earliest Priority Date for ’295, ’662, ’730, ’106, ’002 Patents |
| 2009-11-24 | ’295 Patent Issued |
| 2009-12-15 | ’662 Patent Issued |
| 2010-01-12 | ’730 Patent Issued |
| 2010-03-23 | ’596 Patent Issued |
| 2010-09-07 | ’106 Patent Issued |
| 2010-12-28 | ’002 Patent Issued |
| 2016-04-29 | NIBCO acquires the patents-in-suit |
| 2023-12-20 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 7,621,295 - “System for Controlling Fluid Flow to an Appliance,” issued November 24, 2009
The Invention Explained
- Problem Addressed: The patent describes conventional isolation valves used for in-line appliances as being large, cumbersome, and difficult to install in limited spaces. Furthermore, their designs often do not allow for full fluid flow, which makes accurate testing of the appliance, such as a tankless water heater, difficult (’295 Patent, col. 1:20-39).
- The Patented Solution: The invention is a system comprising two configurable valves—one for the hot water line and one for the cold—to be installed on an appliance. Each valve contains a flow diversion device (e.g., a ball valve) that can be switched between a normal operational mode (connecting the fluid source to the appliance) and a service mode that isolates the appliance and redirects flow to a drain port (’295 Patent, Abstract; col. 2:33-44). This integrated design simplifies draining and flushing for maintenance (’295 Patent, col. 1:53-57).
- Technical Importance: The invention provides a compact, integrated solution for installing and servicing appliances, which is particularly advantageous in the tight physical constraints common in residential and commercial plumbing.
Key Claims at a Glance
- The complaint asserts independent claim 1 and notes infringement of other claims including dependent claims 5 and 9 (Compl. ¶27).
- Independent Claim 1 recites a system with the following essential elements:
- An appliance with an inlet and outlet port.
- A first valve with a first flow port, second flow port, and drain port in a unitary valve body, configurable between a first position (fluid source to appliance inlet) and a second position (appliance inlet to drain port).
- A second valve with a first flow port, second flow port, and drain port in a unitary valve body, configurable between a first position (appliance outlet to plumbing system) and a second position (appliance outlet to drain port).
U.S. Patent No. 7,631,662 - “Hot/Cold Fluid Isolation Valve,” issued December 15, 2009
The Invention Explained
- Problem Addressed: Similar to the ’295 patent, the background highlights the bulky nature and partial flow limitations of existing isolation valves, which complicates appliance installation and maintenance (’662 Patent, col. 1:21-34).
- The Patented Solution: The patent discloses a single, multi-path isolation valve that includes a main flow path, a drain path, and a hot water relief path. A key aspect is a flow diversion device (e.g., a ball valve) configured such that the hot water relief path remains in fluid communication with the primary fluid inlet regardless of whether the valve is in its normal operating or draining configuration (’662 Patent, col. 3:13-28). This provides a persistent safety feature to prevent overpressure conditions (’662 Patent, col. 3:28-33).
- Technical Importance: This design integrates a critical, always-on safety function (pressure relief) into a compact, multi-function valve, improving both safety and serviceability for appliances like tankless water heaters.
Key Claims at a Glance
- The complaint asserts independent claim 1 (Compl. ¶34, ¶35).
- Independent Claim 1 recites a fluid isolation valve with the following essential elements:
- A valve body with a first fluid flow path, a second fluid flow path, a fluid drain path, and a hot water relief path.
- A pressure relief valve in communication with the hot water relief path.
- At least one flow diversion device configurable between two states:
- A first configuration where the first flow path communicates with the second flow path and the hot water relief path.
- A second configuration where the first flow path communicates with the fluid drain path and the hot water relief path.
U.S. Patent No. 7,644,730 - “Method for Isolating an Appliance in a Plumbing System,” issued January 12, 2010
- Technology Synopsis: This patent claims a method for servicing an in-line appliance. The method involves providing a first valve and a second valve, actuating them to isolate the appliance from the fluid source and plumbing system, attaching a flushing mechanism to a drain port, and pumping a flushing fluid through the appliance for cleaning or descaling (’730 Patent, col. 7:20-col. 8:8).
- Asserted Claims: At least claim 1 (Compl. ¶42).
- Accused Features: The complaint alleges that Defendant’s instructions for the Accused Products direct users to perform the steps of the claimed method, thereby inducing infringement (Compl. ¶42).
U.S. Patent No. 7,681,596 - “Isolation Valve with Valve in Drain,” issued March 23, 2010
- Technology Synopsis: This patent describes a fluid isolation valve comprising a main valve portion with a flow diversion device and a separate, adjacent drain valve section. This structure allows the main flow to be diverted to the drain path, while the drain port itself can be independently controlled (opened or closed) by its own valve (’596 Patent, col. 8:12-20).
- Asserted Claims: At least claim 1 (Compl. ¶51, ¶52).
- Accused Features: The physical construction of the Accused Products, which are alleged to embody a main valve portion and a separate, controllable drain valve section (Compl. ¶51, p. 21).
U.S. Patent No. 7,789,106 - “Hot Water Fluid Isolation Valve,” issued September 7, 2010
- Technology Synopsis: This patent discloses a fluid isolation valve containing a flow diversion device, such as a rotatable ball with a through-hole. The configuration is designed to ensure that a hot water relief port remains in fluid communication with the main fluid flow path in both the normal operating configuration and the drain/service configuration, providing a persistent safety feature (’106 Patent, col. 10:1-12).
- Asserted Claims: At least claim 1 (Compl. ¶59, ¶60).
- Accused Features: The internal structure of the Accused Products, specifically the alleged rotatable ball and flow paths that maintain communication with a hot water relief port in multiple configurations (Compl. ¶59, p. 26).
U.S. Patent No. 7,857,002 - “Method for Isolating an Appliance in a Plumbing System,” issued December 28, 2010
- Technology Synopsis: Despite its title, the asserted claim is a system claim similar to that of the ’295 patent. It describes a system for controlling fluid flow to an appliance using a pair of valves (first and second), each having a unitary body and being configurable to switch between connecting a fluid source to the appliance and connecting the appliance to a drain port (’002 Patent, col. 8:5-52).
- Asserted Claims: At least claim 5 (Compl. ¶67, ¶68).
- Accused Features: The Accused Products as a system when used with an appliance, which allegedly provides the claimed dual-valve structure for isolation and draining (Compl. ¶67, p. 28).
III. The Accused Instrumentality
Product Identification
- The accused instrumentalities are "tankless water heaters valves and tankless water heater installation kits," including but not limited to models TWV30X, TWV30RX, TWV3SX, TWV3SRX, TK30RB21-18X, TK30RB21-24X, TK3SRB21-18X, TKS3RB21-24X, TK30RB21-18G3X, TK30RB21-24G3X, and TBV12F (collectively, “Accused Products”) (Compl. ¶22).
Functionality and Market Context
- The Accused Products are valve assemblies intended for installation on the hot and cold water lines of an appliance like a tankless water heater (Compl. ¶22). The complaint's visual evidence, such as the diagram showing an installed valve assembly, depicts products that control water flow during normal operation and can be reconfigured to isolate the appliance for service, allowing it to be drained or flushed via integrated drain ports (Compl. ¶26, p. 7).
IV. Analysis of Infringement Allegations
’295 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A system for isolating and controlling a flow of fluid comprising: an appliance having an inlet port and an outlet port; | The Accused Products are shown installed on a tankless water heater appliance. | ¶26, p. 7 | col. 2:45-53 |
| a first valve having a first flow port, a second flow port, and a drain port formed in a unitary valve body, | The accused valve has a single-piece body with ports for fluid source, appliance connection, and draining. A diagram shows these ports on an exemplary product. | ¶26, p. 7, 9 | col. 2:21-32 |
| said first flow port of said first valve in fluid communication with a fluid source and said second flow port said first valve in fluid communication with said inlet port of said appliance, | The valve is alleged to connect a fluid source to the appliance's inlet port for normal operation. | ¶26, p. 7 | col. 2:21-26 |
| said first valve being configurable between a first and second position in the unitary valve body, | The valve's handle can be turned to switch between two positions, as illustrated in a product photo with a curved arrow. | ¶26, p. 8 | col. 2:36-39 |
| when said first valve is in said first position said fluid source is in fluid communication with said appliance | In the first position, a diagram shows a flow path from the fluid source, through the valve, to the appliance. | ¶26, p. 8 | col. 2:40-42 |
| and when said first valve is in said second position said appliance is in fluid communication with said drain port of said first valve; | In the second position, a diagram depicts a flow path from the appliance through the valve to the drain port. | ¶26, p. 9 | col. 2:42-44 |
| and a second valve having a first flow port, a second flow port and a drain port formed in a unitary valve body, | The system includes a second, similar valve, shown in product photos, alleged to be for the hot water side of the appliance. | ¶26, p. 9 | col. 8:38-41 |
- Identified Points of Contention:
- Scope Questions: A potential issue is the scope of "unitary valve body." The question may arise whether this term requires a single monolithic casting or if it can read on a body made of multiple components that are permanently joined (e.g., brazed or welded) to form a single functional unit.
- Technical Questions: The complaint's infringement theory relies on diagrams with overlaid arrows to show fluid paths. The actual internal fluid dynamics of the Accused Products will require expert analysis to confirm they match the specific communication paths required by the claims in each configuration.
’662 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A fluid isolation valve comprising: a valve body having a first fluid flow path, a second fluid flow path, a fluid drain path, a hot water relief path... | The accused valve body is alleged to contain pathways for normal flow, draining, and pressure relief. | ¶34, p. 13 | col. 3:3-8 |
| ...and a pressure relief valve in communication with said hot water relief path; | The accused valve includes a port for a pressure relief valve, which is shown in the product photograph. | ¶34, p. 13 | col. 3:28-33 |
| ...and at least one flow diversion device configurable between a first configuration and a second configuration, | The accused valve has a handle that operates an internal flow diversion device to switch between two operational modes. | ¶34, p. 13 | col. 5:19-21 |
| such that when the flow diversion device is in the first configuration the first fluid flow path is communicated with the second fluid flow path and the hot water relief path, | In the normal operating position, a diagram alleges a fluid path from the inlet to both the outlet and the relief path. | ¶34, p. 13 | col. 5:21-25 |
| and when the flow diversion device is in the second configuration, the first fluid flow path is communication with the fluid drain path and the hot water relief path. | In the service position, a diagram alleges a fluid path from the inlet to both the drain path and the relief path. | ¶34, p. 13-14 | col. 5:25-28 |
- Identified Points of Contention:
- Technical Questions: The central technical question is whether the Accused Product's "hot water relief path" is in communication with the "first fluid flow path" in both configurations as claimed. The complaint's diagrams (Compl. ¶34, p. 13) assert this, but verifying the internal fluidics of the actual product will be a key evidentiary issue. The precise nature of this "communication" may become a focus of the dispute.
V. Key Claim Terms for Construction
Term 1: "unitary valve body" (’295 Patent, Claim 1)
- Context and Importance: This term appears in the system claims of both the ’295 and ’002 patents. Its construction is critical because if the accused valves are not considered "unitary," a core element of the claims would not be met. Practitioners may focus on this term to determine if a valve assembled from multiple permanently-fixed pieces falls within the scope, or if it is limited to a single, monolithic piece.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification does not explicitly define "unitary." A party could argue for its plain and ordinary meaning, which might encompass an assembly that functions as a single, inseparable unit.
- Evidence for a Narrower Interpretation: The figures, such as Figure 1 of the ’295 patent, depict a valve body that appears to be a single forged or cast piece. A party could argue that the invention is limited to these embodiments, suggesting "unitary" means formed from a single, continuous piece of material.
Term 2: "communicated with" (’662 Patent, Claim 1)
- Context and Importance: Claim 1 of the ’662 patent requires the "first fluid flow path" to be "communicated with" the "hot water relief path" in both valve configurations. The meaning of "communicated with"—whether it requires a direct, unobstructed path or allows for an indirect or partial connection—will be central to the infringement analysis for this patent.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent's objective is to provide an "important safety feature" by preventing overpressure (’662 Patent, col. 3:28-33). A party may argue that any fluid connection sufficient to achieve this safety function meets the "communicated with" requirement.
- Evidence for a Narrower Interpretation: A party may argue that the specific language requires the first fluid flow path itself to be directly connected to the relief path, as opposed to both simply being open to a common chamber. The patent's description of the flow diversion device's internal channels could be used to argue for a specific, direct type of communication (’662 Patent, col. 5:30-col. 6:53).
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement for all asserted patents (e.g., Compl. ¶27, ¶35). For the method claims of the ’730 patent, the complaint specifically alleges inducement by asserting that "The instructions provided by BrassCraft tell users to" perform the patented steps (Compl. ¶42).
- Willful Infringement: Willfulness is alleged for all six patents. The complaint alleges that "BrassCraft had actual knowledge" of each patent and "acted recklessly and in complete disregard" of NIBCO's rights (e.g., Compl. ¶29, ¶37, ¶70). The complaint does not, however, plead specific facts detailing how or when this alleged pre-suit knowledge was obtained.
VII. Analyst’s Conclusion: Key Questions for the Case
- A primary issue will be one of claim construction and structural scope: Can the term "unitary valve body," as used in the ’295 and ’002 patents, be construed to cover valve bodies assembled from multiple permanently-joined components, or is it limited to a single monolithic piece as depicted in the patent figures? The answer will significantly impact the infringement analysis for a substantial portion of the asserted patent portfolio.
- A key evidentiary question will be one of functional fidelity: Do the internal fluidics of the Accused Products perform the exact functions recited in the claims? Specifically for the ’662 and ’106 patents, does the hot water relief path remain in communication with the "first fluid flow path" in both valve configurations, or is there a subtle but material difference in operation that could support a non-infringement defense?
- Finally, a central procedural question will concern willfulness: The complaint makes conclusory allegations of "actual knowledge" for all six patents. A critical issue will be whether Plaintiff can produce evidence of pre-suit notice or other facts to substantiate these claims, which are a prerequisite for seeking enhanced damages.