DCT

2:11-cv-00037

Enpac LLC v. Lucas

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I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 2:11-cv-00037, W.D. Wash., 01/07/2011
  • Venue Allegations: Venue is alleged to be proper as both defendants reside in the judicial district.
  • Core Dispute: Plaintiff seeks a declaratory judgment that its catch basin insert products do not infringe Defendant’s patent, and further that the patent is invalid and unenforceable due to an alleged prior sale of the patented invention and inequitable conduct before the U.S. Patent and Trademark Office (USPTO).
  • Technical Context: The technology concerns filter systems placed inside storm water catch basins to remove debris, sediment, and other pollutants from runoff water before it enters the public drainage system.
  • Key Procedural History: The complaint’s central allegation is that the patentee, Ms. Lucas, placed her own invention on sale and described it in a public trademark filing in 2004, more than one year before filing the patent application in 2007. The complaint alleges this prior art was material and was not disclosed to the USPTO during patent prosecution, forming the basis for claims of invalidity under the on-sale bar and unenforceability due to inequitable conduct.

Case Timeline

Date Event
2002-XX-XX Plaintiff Enpac begins selling its STORM SENTINEL product.
2004-XX-XX Defendant Lucas's SEA LIFE SAVER product is allegedly on sale.
2004-XX-XX Defendant Lucas files a trademark application "specimen" allegedly depicting the SEA LIFE SAVER product.
2007-10-23 Priority date of U.S. Patent No. 7,771,591.
2010-08-10 U.S. Patent No. 7,771,591 issues.
2010-08-10 (post) Defendants allegedly contact Plaintiff's customers asserting infringement.
2010-10-29 Plaintiff sends cease-and-desist letter to Defendants regarding infringement allegations.
2010-10-30 Defendants allegedly reaffirm infringement allegations.
2011-01-07 Complaint for Declaratory Judgment filed.

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

U.S. Patent No. 7,771,591 - “Filter System for Catch Basins,” issued August 10, 2010

The Invention Explained

  • Problem Addressed: The patent addresses the problem of drainage water in common catch basins containing debris, contaminants, oil, and grease, which are undesirable to release into the public water system. (’591 Patent, col. 1:11-19).
  • The Patented Solution: The invention is a filter system designed to be installed inside a catch basin to capture contaminants. The core of the patented solution is a rigid "filter basket" with a specific two-flange rim structure. An outwardly directed upper flange rests on the catch basin's grate-supporting shoulder, while an inwardly directed lower flange, spaced below the upper flange, can support additional filter elements like a secondary basket or a liner. (’591 Patent, Abstract; col. 1:36-46). This structure is illustrated in, for example, Figure 3 of the patent.
  • Technical Importance: The described system provides a removable and maintainable method for filtering storm runoff at the point of entry, intended to be an effective and economic solution to prevent pollutants from entering drainage pipe networks. (’591 Patent, col. 1:19-26).

Key Claims at a Glance

  • The complaint identifies independent claims 1 and 17 as being asserted. (Compl. ¶29).
  • Independent Claim 1 recites a filter system for a catch basin comprising:
    • At least one filter device comprising a larger filter basket.
    • The filter basket includes horizontal and vertical frame members and pervious side and bottom walls.
    • An upper rim with an "outwardly directed upper rim flange" to sit on the catch basin's shoulder.
    • An "inwardly directed lower rim flange" spaced below the upper flange.
    • A "vertical wall" extending between the upper and lower flanges.
    • "Vertically upwardly extending posts" on the lower rim flange.
  • Independent Claim 17 recites a similar system that requires:
    • "at least a larger filter basket" with the same frame, wall, and flange structure as in Claim 1.
    • "a second filter basket" that sits down into the larger filter basket.
  • The complaint also seeks a declaratory judgment of non-infringement of dependent claims 2-16 and 18-21. (Compl. ¶40).

III. The Accused Instrumentality

Product Identification

  • The accused products are Enpac’s “STORM SENTINEL brand adjustable catch basin inserts.” (Compl. ¶5).

Functionality and Market Context

  • The complaint describes the STORM SENTINEL product sold since August 10, 2010, as consisting of a "single fabric sheet that at its perimeter edge surrounds and at least partially encases an adjustable rod mechanism." (Compl. ¶37). This fabric sheet hangs from the rod mechanism to form a filter. The complaint alleges the product does not have a "filter basket having horizontal and vertical frame members" or the specific flange structures required by the patent claims. (Compl. ¶38). The complaint includes an image from a 2010 product catalog showing the installation and removal of the STORM SENTINEL insert, which depicts a flexible filter body being fitted into a catch basin recess. (Compl. ¶36).

IV. Analysis of Infringement Allegations

The complaint seeks a declaratory judgment of non-infringement. The analysis below summarizes the plaintiff's core arguments for why its product does not meet the limitations of the asserted claims.

'591 Patent Infringement Allegations

Claim Element (from Independent Claim 1) Alleged Non-Infringing Functionality Complaint Citation Patent Citation
a filter basket (22) comprising horizontal and vertical frame members and pervious side and bottom walls secured to the frame members The STORM SENTINEL product allegedly has no such filter basket, instead consisting of a "single fabric sheet" hanging from an "adjustable rod mechanism." ¶¶37-38 col. 5:55-58
an upper rim including an outwardly directed upper rim flange adopted to set down onto the grate supporting shoulder of the catch basin The product's adjustable rod mechanism is "adapted to be captured between the shoulder of a catch basin and a grate," but the complaint alleges this structure is distinct from the claimed flange. ¶37 col. 5:58-62
an inwardly directed lower rim flange spaced below the upper flange The complaint alleges this limitation is not present in the STORM SENTINEL product, which is described as a hanging fabric sheet without a lower flange structure. ¶39 col. 6:1-3
a vertical wall extending between the upper and lower rim flanges The complaint alleges this limitation is not present, as the product lacks the claimed upper and lower flanges between which a wall could extend. ¶39 col. 6:3-5
said lower rim flange including vertically upwardly extending posts spaced laterally from the vertical wall The complaint alleges this limitation is not present, as the product lacks the claimed lower rim flange from which posts could extend. ¶39 col. 6:5-7
  • Identified Points of Contention:
    • Structural Mismatch: The primary point of contention is a fundamental structural difference. The complaint alleges the '591 patent claims a rigid, framed basket with specific upper and lower flanges, while the accused STORM SENTINEL is a flexible fabric bag suspended from an adjustable rod frame. (Compl. ¶¶ 37-38). A key visual from the complaint shows the "SEA LIFE SAVER" prior art product, which appears structurally similar to the patent's figures, placed side-by-side with Figure 3 from the '591 patent itself, highlighting their alleged identity. (Compl. p. 6).
    • Scope Questions: A central question for the non-infringement analysis will be whether the claim term "filter basket" can be construed broadly enough to read on a flexible fabric bag supported by a rod mechanism, or if it is limited by the specification to the rigid, framed structure with specific flanges as depicted. (Compl. ¶38).

V. Key Claim Terms for Construction

  • The Term: "filter basket"
  • Context and Importance: The definition of this term is critical. Enpac's non-infringement defense hinges on its argument that its flexible "fabric sheet" on a "rod mechanism" is not a "filter basket" as claimed. (Compl. ¶¶ 37-38). The patentee would need to argue for a broader construction that covers Enpac's design. Practitioners may focus on this term because the entire non-infringement case appears to turn on whether the accused product’s structure falls within its scope.
  • Intrinsic Evidence for Interpretation:
    • Evidence for a Broader Interpretation: The patent's stated purpose is to provide a "filter system for removing debris and contaminants." (’591 Patent, col. 1:6-8). A party could argue that any structure performing this function within a catch basin should be considered a "filter basket" in the context of the invention.
    • Evidence for a Narrower Interpretation: Claim 1 requires the "filter basket" to comprise "horizontal and vertical frame members," an "outwardly directed upper rim flange," and an "inwardly directed lower rim flange." (’591 Patent, col. 5:56-col. 6:3). The patent specification consistently depicts and describes a rigid, box-like structure made of materials like "expanded metal" and "angle iron." (’591 Patent, Fig. 3; col. 3:33-37). This evidence may support limiting the term to a structure possessing these specific, rigid components.

VI. Other Allegations

  • Invalidity and Unenforceability (Inequitable Conduct): The complaint makes detailed allegations that the '591 patent is invalid and/or unenforceable.
    • Basis: The complaint alleges that the inventor, Ms. Lucas, sold and publicly disclosed a product called the "SEA LIFE SAVER" as early as 2004, which embodies the invention claimed in the '591 patent. (Compl. ¶¶ 12, 27). This activity occurred more than one year prior to the patent application's filing date of October 23, 2007, which could create an on-sale bar to patentability under 35 U.S.C. §102(b). (Compl. ¶¶ 23-24).
    • Evidence: The complaint provides a photograph of the alleged prior art product, which was submitted by Ms. Lucas to the USPTO in 2004 as a "specimen" for a trademark application. (Compl. ¶13). The complaint alleges this product is "identical" to the filter basket illustrated in the '591 patent. (Compl. p. 6).
    • Alleged Concealment: The complaint alleges that Ms. Lucas never submitted an Information Disclosure Statement (IDS) to the patent examiner disclosing these prior sales or the public "specimen," despite having a duty to disclose all information material to patentability. (Compl. ¶26). This alleged failure to disclose is the basis for the inequitable conduct claim.

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

  1. Invalidity and Unenforceability: The central issue appears to be whether the patent is invalid or unenforceable due to the inventor's alleged pre-filing commercial activity. This will involve two key factual and legal determinations: first, whether the "SEA LIFE SAVER" product was in public use or on sale before the critical date, and second, whether the inventor intentionally withheld this material information from the USPTO with an intent to deceive.

  2. Claim Construction: Should the patent survive the invalidity and unenforceability challenges, the case will turn on a question of definitional scope. Can the term "filter basket", which is described in the patent with specific rigid structural elements like frames and dual flanges, be construed to cover the plaintiff's accused product, which is described as a flexible fabric sheet suspended from an adjustable rod mechanism?

  3. Evidentiary Proof: A key evidentiary question will be one of structural identity: does the evidence, particularly the 2004 trademark specimen photograph, establish that the prior art "SEA LIFE SAVER" product is the same as the invention claimed in the '591 patent? The complaint's side-by-side visual comparison of the prior art photo and a patent figure suggests this will be a primary focus of litigation. (Compl. p. 6).