DCT

2:25-cv-00943

Blueridge Fiber Solutions LLC v. Complete Filter Media LLC

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:25-cv-00943, S.D. Ohio, 08/20/2025
  • Venue Allegations: Plaintiff alleges venue is proper in the Southern District of Ohio because Defendant is an Ohio company that resides in the district and has allegedly committed acts of patent infringement in Ohio.
  • Core Dispute: Plaintiff alleges that Defendant’s fiberglass filtration media products are manufactured using methods and apparatuses that infringe four of Plaintiff's patents related to the production of continuous glass filament media.
  • Technical Context: The dispute centers on the manufacturing technology for fiberglass filtration media, a product used in applications such as commercial HVAC systems and paint overspray capture.
  • Key Procedural History: The complaint alleges a competitive history where Plaintiff's predecessor, Superior Fibers, and Defendant were rivals. Plaintiff alleges that Defendant hired a former Plant Manager and a former Executive Officer from Superior Fibers, acquired Superior Fibers' bushing plate supplier, and purchased bushing plates built to Superior Fibers' exact specifications. The complaint also notes that Plaintiff's predecessor sent written notice letters to Defendant regarding its patent portfolio on March 12, 2018, and again on January 28, 2020, before Plaintiff acquired the patents-in-suit and filed this action.

Case Timeline

Date Event
2014-02-14 Earliest Priority Date for ’452, ’427, and ’876 Patents
2015-05-11 Earliest Priority Date for ’462 Patent
2018-03-12 Plaintiff’s predecessor allegedly provides written notice of patent portfolio to Defendant
2018-05-15 U.S. Patent No. 9,968,876 issues
2018-10-23 U.S. Patent No. 10,106,452 issues
2019-07-16 U.S. Patent No. 10,351,462 issues
2019-11-26 U.S. Patent No. 10,487,427 issues
2020-01-28 Plaintiff’s predecessor allegedly sends second notice letter to Defendant
2024-05-23 Plaintiff acquires patents-in-suit from Superior Fibers
2025-04-29 Alleged start date of conference where Accused Products were displayed
2025-08-20 Complaint Filing Date

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

U.S. Patent No. 10,351,462 - "Method of Manufacturing Fiberglass Filtration Media," issued July 16, 2019

The Invention Explained

  • Problem Addressed: The patent's background describes the problem of "face loading" in existing paint arrestor media, where paint droplets are captured primarily at the surface, causing the filter to clog prematurely. This creates a need for paint arrestors with improved paint holding capabilities. (’462 Patent, col. 1:57 - col. 2:24).
  • The Patented Solution: The invention is a method for manufacturing fiberglass media that creates a progressive density throughout the filter's depth. This is achieved by controlling the speed of a glass melter as it traverses a rotating drum, using sets of fast and slow passes. The resulting fiberglass mat is then expanded, passed through rollers, sprayed with a liquid, and cured, creating a final product with coarse, wavy filament bundles on the air-intake side and progressively denser, finer bundles toward the air-exit side. (’462 Patent, Abstract; col. 3:1-12).
  • Technical Importance: This method creates a filter structure that captures larger particles near the more open surface and smaller particles deeper within the denser media, thereby increasing the filter's overall capacity and useful life. (’462 Patent, col. 2:55-62).

Key Claims at a Glance

  • The complaint asserts independent claim 1. (Compl. ¶29).
  • The essential elements of claim 1, a method claim, are:
    • Providing glass into a melter coupled to a specifically oriented bushing plate (5 to 7 degree angle) having a specific number of orifices (298 to 425).
    • Traversing the melter back and forth above a rotating drum to define a pass.
    • Depositing the resulting glass filament strands onto the drum.
    • Traversing the melter at a first speed and a second speed.
    • Spraying binder onto the strands to form a mat.
    • Removing the mat and providing it to a let-off table with a conveyor.
    • Expanding the mat to produce a specific structure with wavy, bundled filaments on the air entrance side and progressively denser, less wavy bundles toward the air exit side.
    • Providing the expanded mat through an upper and lower roller apparatus.
    • Spraying liquid onto the bottom side of the mat.
    • Curing the mat in a curing apparatus.
  • The complaint reserves the right to assert additional claims, including claims 2 and 7. (Compl. ¶36, ¶70).

U.S. Patent No. 10,106,452 - "System and Method of Continuous Glass Filament Manufacture," issued October 23, 2018

The Invention Explained

  • Problem Addressed: The patent's background identifies several challenges in the traditional "Modigliani process" for manufacturing fiberglass, including difficulty in controlling the product's final loft (thickness), achieving proper cross-linking of filaments for stiffness, and preventing binder from migrating unevenly due to centrifugal forces on the rotating drum. (’452 Patent, col. 1:53 - col. 2:58).
  • The Patented Solution: The invention is an apparatus designed to improve control over the manufacturing process. Key features include a temperature-controlled reservoir for the binder, a traversing glass melting furnace, a bushing plate made of a specific material ("Inconel"), and one or more shields positioned below the bushing plate. These shields are configured to enclose no more than three sides, which helps control ambient air flow that could otherwise disrupt the falling glass filaments. (’452 Patent, Abstract; col. 3:2-24).
  • Technical Importance: The claimed apparatus provides a set of specific, integrated controls over heat, material composition, and airflow to address known inconsistencies in fiberglass media production, aiming to improve product quality and manufacturing efficiency. (’452 Patent, col. 2:59-63).

Key Claims at a Glance

  • The complaint asserts independent claim 1. (Compl. ¶40).
  • The essential elements of claim 1, an apparatus claim, are:
    • A reservoir for binder, configured to control temperature.
    • A rotatable drum.
    • A traversing glass melting furnace.
    • A bushing plate coupled to the furnace, consisting of Inconel, with orifices to spin filaments.
    • A combustion heat source positioned above the bushing plate.
    • A binder sprayer coupled to the furnace.
    • One or more shields coupled to and extending vertically below the bushing plate.
    • Wherein the shields enclose no more than three sides below the plate, leaving at least one side open.
  • The complaint reserves the right to assert additional claims, including claims 2, 3, 15, and 16. (Compl. ¶46, ¶80).

Multi-Patent Capsule: U.S. Patent No. 10,487,427 - "System and Method for Continuous Strand Fiberglass Media Processing," issued November 26, 2019

  • Technology Synopsis: This patent discloses a method for processing fiberglass media to control the final product's physical properties. The described problem involves the difficulty of achieving consistent skin characteristics on the fiberglass mat. The patented solution involves applying a liquid consisting of water to the mat as it passes through a roller apparatus immediately before it enters a curing oven. (’427 Patent, Abstract; col. 2:2-10).
  • Asserted Claims: Independent claim 1. (Compl. ¶50).
  • Accused Features: Plaintiff alleges Defendant's manufacturing method infringes by providing a fiberglass mat through a roller apparatus, applying a liquid consisting of water to it, and immediately curing it in an oven. (Compl. ¶51, ¶55).

Multi-Patent Capsule: U.S. Patent No. 9,968,876 - "Method of Manufacturing Fiberglass Filtration Media," issued May 15, 2018

  • Technology Synopsis: This patent is directed to methods for making high-capacity paint arrestance media. The technical solution involves controlling a melter's traverse speed over a rotating drum—using a faster second speed—to form a fiberglass mat with progressive density. The method also includes an expansion step and a step of passing the mat through a spray and roller apparatus to create a specific "air exit skin" comprising 7.5% to 25% of the mat's total weight. (’876 Patent, Abstract; col. 2:28-41).
  • Asserted Claims: Independent claim 1. (Compl. ¶60).
  • Accused Features: Plaintiff alleges Defendant's manufacturing method infringes by traversing a melter at different speeds (with the second being faster), expanding the mat to create a progressively denser structure, and forming a final product with an air exit skin having the claimed characteristics. (Compl. ¶61, ¶65).

III. The Accused Instrumentality

Product Identification

  • The complaint identifies the accused instrumentalities as "one or more fiberglass media products (the 'Accused Products')" manufactured and offered for sale by Defendant CFM. (Compl. ¶25).

Functionality and Market Context

  • The Accused Products are described as fiberglass filtration media. (Compl. ¶15). The complaint alleges that Defendant made a "calculated decision to copy" the products and methods of Plaintiff's predecessor, Superior Fibers, to sell "identical or nearly identical products in the marketplace." (Compl. ¶15). It further alleges that samples of the Accused Products were made available for inspection at the FiltXPO International Filtration Conference & Exhibition from April 29, 2025 to May 1, 2025. (Compl. ¶26). The complaint does not provide further technical detail on the specific structure or function of the final Accused Products themselves, focusing instead on the alleged method and apparatus of their manufacture.

IV. Analysis of Infringement Allegations

10,351,462 Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
providing glass into a melter coupled to a bushing plate... wherein the bushing plate is oriented at a 5 to 7 degree angle... and further wherein the bushing plate comprises 298 to 425 orifices Defendant allegedly uses bushing plates meeting these exact specifications, acquired from a supplier that previously manufactured them for Plaintiff's predecessor. ¶31 col. 6:5-12
traversing the melter... to define a pass; depositing the glass filament strands onto the rotating drum; traversing the melter in one or more passes at a first speed; traversing the melter in one or more passes at a second speed Defendant is alleged to practice each of the steps recited in the claim, based on knowledge allegedly obtained from a former Plant Manager of Plaintiff's predecessor. ¶32, ¶35 col. 6:13-22
expanding the fiberglass mat to produce an expanded fiberglass mat comprising bundled filaments on an air entrance side... that are wavy... and progressively denser and less wavy... toward an air exit side Defendant's former Plant Manager was allegedly familiar with this specific method of expanding the mat to create the claimed structure. ¶32, ¶35 col. 6:30-41
providing the expanded fiberglass mat through a roller apparatus... spraying liquid onto the bottom side of the expanded fiberglass mat; and curing the expanded fiberglass mat Defendant's former Plant Manager was allegedly familiar with these specific processing steps. ¶32, ¶35 col. 6:42-48

10,106,452 Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Infringing Functionality Complaint Citation Patent Citation
An apparatus for manufacture of continuous glass filament filtration media, comprising: a reservoir comprising binder and configured to control a temperature of the binder Defendant allegedly uses an apparatus with this feature, based on knowledge allegedly obtained from a former Plant Manager of Plaintiff's predecessor. ¶43, ¶44 col. 8:14-16
a rotatable drum; a traversing glass melting furnace... a binder sprayer coupled to the traversing glass melting furnace The complaint alleges Defendant's apparatus contains these features, based on the knowledge of the former employee. ¶43, ¶44 col. 8:17-25
a bushing plate coupled to the traversing glass melting furnace, the bushing plate consisting of Inconel Defendant allegedly uses a bushing plate "consisting of Inconel" as previously specified by Plaintiff's predecessor to its supplier. ¶42 col. 8:20-22
one or more shields coupled to the bushing plate... wherein the one or more shields enclose no more than three sides below the bushing plate so that at least one side remains open Defendant's former Plant Manager was allegedly familiar with the use of shields enclosing three sides below the bushing plate. ¶43, ¶44 col. 8:26-31

No probative visual evidence provided in complaint.

  • Identified Points of Contention:
    • Evidentiary Questions: The complaint's infringement allegations rely heavily on "information and belief" and knowledge imputed to the Defendant through a hired former employee of Plaintiff's predecessor. A central point of contention may be what factual evidence Plaintiff can produce to demonstrate that Defendant's manufacturing process and apparatus meet every limitation of the asserted claims, rather than just possessing general similarities.
    • Scope Questions: For the ’462 patent, a key question will be whether Defendant's process creates a mat with the specific claimed structure of "bundled filaments... that are wavy in three dimensions and progressively denser and less wavy." For the ’452 patent, which is an apparatus claim, the dispute may focus on whether Defendant makes, uses, or sells an apparatus containing all claimed elements, including the specific "consisting of Inconel" bushing plate and the "shields... enclos[ing] no more than three sides."

V. Key Claim Terms for Construction

  • The Term: "expanding the fiberglass mat to produce an expanded fiberglass mat comprising bundled filaments... that are wavy... and progressively denser" (’462 Patent, Claim 1)

    • Context and Importance: This term recites the specific, complex structure of the final product. Infringement of this method claim depends on whether the accused process results in a product that meets this structural definition. The definition of what constitutes "wavy," "bundled," and "progressively denser" will be critical.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The specification describes this as a general outcome of the expansion and curing process, suggesting it may cover a range of resulting structures. For example, it states the lofting process "provides geometries of the bonded glass filaments suitable for paint arrestors." (’462 Patent, col. 2:34-36).
      • Evidence for a Narrower Interpretation: The patent provides specific descriptions and figures illustrating the intended structure. Figure 1 is a perspective view showing "coarse bundles... forming a generally wavy pattern on the air intake side" and "progressively denser, finer bundles" approaching the exit side, which could be used to argue for a more limited construction tied to that depiction. (’462 Patent, col. 3:24-28).

  • The Term: "a bushing plate... consisting of Inconel" (’452 Patent, Claim 1)

    • Context and Importance: The term "consisting of" is a term of art in patent law that typically closes the claim element to any materials other than what is recited. The dispute will turn on whether Defendant's bushing plate is made exclusively of Inconel, or if it contains other materials that would place it outside the scope of the claim.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: A party might argue that in the context of materials science, "Inconel" refers to a family of nickel-chromium-based superalloys, not a single pure substance, potentially allowing for minor variations in composition. The patent does not define the term further.
      • Evidence for a Narrower Interpretation: The use of "consisting of" creates a strong presumption that the claim is closed. The specification states "Molten glass exits the melting furnace 10 through an Inconel bushing plate," without mentioning any other materials or alloys, which may support a narrow interpretation. (’452 Patent, col. 4:45-46).

VI. Other Allegations

  • Indirect Infringement: The complaint does not plead a separate count for indirect infringement. However, it alleges facts that could be relevant to establishing knowledge and intent, such as Defendant's alleged hiring of Plaintiff's predecessor's former Plant Manager and Executive Officer, who were allegedly familiar with the patented methods. (Compl. ¶21-23, ¶32, ¶43).
  • Willful Infringement: Willfulness is alleged for all four patents-in-suit. (Compl. ¶72, ¶82, ¶92, ¶102). The complaint bases this allegation on alleged pre-suit knowledge of the patents, citing two specific written notice letters sent by Plaintiff's predecessor to Defendant on March 12, 2018, and January 28, 2020. (Compl. ¶19, ¶24, ¶37).

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

The resolution of this case may turn on the following central questions:

  • A primary issue will be one of evidentiary proof: The complaint's theory is built on allegations of wholesale copying, supported by the hiring of former employees and the use of a common supplier. A key question for the court will be whether the factual evidence, once produced, demonstrates that Defendant’s accused manufacturing methods and apparatus meet every limitation of the asserted claims, or if the allegations are based on inference and similarity alone.
  • A second core issue will be one of technical and definitional scope: Can Plaintiff show that the accused manufacturing process creates the specific, multi-part structure of "progressively denser and less wavy bundles" as required by claim 1 of the ’462 patent? Similarly, for the apparatus claim of the ’452 patent, does the use of the term "consisting of Inconel" limit the claim to a specific material composition that Defendant's bushing plate may or may not meet?