PTAB

PGR2025-00048

Milwaukee Electric Tool Corp v. Klein Tools Inc

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Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Luminescent Fish Tape System
  • Brief Description: The ’573 patent relates to a fish tape system used to pull electrical wires through conduits. The system features a fish tape made with a luminescent material housed within a case, where at least a portion of the case is configured to allow light to pass through and energize the luminescent material, enhancing its visibility in dark environments.

3. Grounds for Unpatentability

Ground 1: Obviousness over Hartranft and Bruin - Claims 1-4, 6-12, and 14-18 are obvious over Hartranft in view of Bruin.

  • Prior Art Relied Upon: Hartranft (European Patent No. 1,391,412) and Bruin (International Publication No. WO 1997/41626).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued Hartranft taught the core elements of the claimed system, including a fish tape housed in a "donut shaped" case with translucent or transparent sidewalls and a handle for deployment. Hartranft’s translucent housing inherently allows light to pass through. Bruin taught that a flexible element for pulling cables, such as a tape, could be manufactured with or marked by a fluorescent (a type of luminescent) material to make it easier to locate in dark wall cavities. The combination of Hartranft’s fish tape system with Bruin’s luminescent tape allegedly rendered the claims obvious.
    • Motivation to Combine: A person of ordinary skill in the art (POSA) would combine these references to solve the known problem of poor fish tape visibility in dark conduits. Petitioner asserted a POSA would apply the known technique from Bruin (making the tape luminescent) to improve the known device in Hartranft (the fish tape system) for its intended purpose. This amounts to a simple substitution of a known element (a standard tape) with another (a luminescent tape) to obtain predictable results.
    • Expectation of Success: A POSA would have a reasonable expectation of success because incorporating a luminescent material onto a fish tape was a simple modification that would not alter the mechanical function of Hartranft’s device but would predictably improve its visibility when used in dark spaces.

Ground 2: Obviousness over Klein Fish Tape Publication (KP1) and Southwire Publication (SP1) - Claims 1-18 are obvious over KP1 in view of SP1.

  • Prior Art Relied Upon: KP1 (Klein Fish Tape Publication) and SP1 (Southwire Glow in the Dark Fish Sticks Publication).

  • Core Argument for this Ground:

    • Prior Art Mapping: Petitioner contended that KP1, a product instruction manual, disclosed a complete fish tape system with a case, handle, and a fish tape with a threaded end. Crucially, KP1’s case included multiple "viewports"—cutouts in the sidewalls—that allow a user to see the tape inside. SP1 disclosed "glow in the dark" (luminescent) fiberglass rods used for pulling wires. Petitioner argued that combining SP1's luminescent material with KP1's system rendered the claims obvious, as the viewports in KP1’s case would function as the claimed configuration allowing light to energize the luminescent tape.
    • Motivation to Combine: A POSA would be motivated to add the luminescent properties of SP1 to the fish tape in KP1's system to improve safety and efficiency. KP1’s instructions caution about the dangers of working near live circuits and the problem of the tape getting hung up, both of which are mitigated by increased visibility. A POSA would look to known solutions like the glow-in-the-dark technology in SP1 to improve KP1's device. The viewports in KP1 already provide a natural means for light to energize the tape.
    • Expectation of Success: Success was expected because applying luminescent material to electrician's tools was a well-known process. Substituting the standard steel tape in KP1 with a luminescent one from SP1, or coating the existing tape, was a simple modification expected to work as intended.

  • Additional Grounds: Petitioner asserted obviousness for claims 5 and 13 by adding Noonan (Patent 5,505,432) to the Hartranft and Bruin combination to teach a fish tape with a threaded opening. Petitioner also challenged claims 1-18 for lack of written description under 35 U.S.C. §112(a), arguing the claim term "configured" is impermissibly broader than the specification’s sole disclosure of a "transparent" case. Finally, Petitioner challenged claims 1-13 as indefinite under 35 U.S.C. §112(b), arguing the term "donut shaped" is subjective and lacks an objective standard in the specification to inform a POSA of its scope with reasonable certainty.

4. Relief Requested

  • Petitioner requests institution of Post-Grant Review and cancellation of claims 1-18 of the ’573 patent as unpatentable.