PTAB

IPR2015-01461

Milwaukee Electric Tool Corp v. Irwin Industrial Tool Co

Log In
Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Hole Cutter with Fulcrums for Work Piece Slug Removal
  • Brief Description: The ’554 patent discloses a hole saw with a cylindrical blade body having at least one axially-elongated aperture. The aperture defines multiple fulcrums, allowing a user to insert a tool (like a screwdriver) to pry out work piece slugs that become lodged inside the saw after cutting.

3. Grounds for Unpatentability

Ground 1: Anticipation of Claims 1, 3-5, 14-18, 20, 22-28, 32, 34, and 36-37 by Redford

  • Prior Art Relied Upon: Redford (Patent 7,237,291).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that Redford, which discloses a combined nut driver and debris removing tool, teaches every element of the challenged claims. Redford's "cleaning flange" is described as "essentially a hole saw" and includes a continuous, S-shaped channel that functions as the claimed axially-elongated aperture. Petitioner asserted that the depressions and surfaces within this channel (specifically upper depression 53, lower depression 55, and an intermediate surface) are structurally identical to the claimed first, second, and third fulcrums, arranged at different axial distances from the cutting edge to facilitate slug removal.
    • Key Aspects: The core of this ground relied on construing the functional language in the claims (e.g., "configured to receive... a lever") as not imposing a structural limitation beyond the inherent capability of Redford's disclosed device. Petitioner contended that Redford's S-shaped channel is inherently capable of receiving a lever to pry slugs, thus anticipating the claims.

Ground 2: Obviousness of Claims 2, 6-13, 21, 29, 33, and 35 over Redford in view of Starbuck

  • Prior Art Relied Upon: Redford (Patent 7,237,291) and Starbuck (Patent 2,473,077).
  • Core Argument for this Ground:
    • Prior Art Mapping: Redford was asserted to teach the basic hole saw with a single, continuous S-shaped aperture containing multiple fulcrums. Starbuck taught a conventional hole cutter with multiple, angled slots for chip removal, disclosing that providing two or more slots is well known. Petitioner argued that the combination addressed limitations requiring multiple apertures (claims 2, 33) and specific slot orientations (claims 6-9, 29), such as being angled relative to the axis of rotation.
    • Motivation to Combine: A POSITA would combine Redford and Starbuck to improve the functionality of Redford's tool. Specifically, a POSITA would find it obvious to add the well-known chip removal slots of Starbuck to the hole saw of Redford to aid in the removal of cuttings, a known technique to improve a similar device. Petitioner argued it would have been an obvious design choice to merge Redford’s S-shaped slot with Starbuck’s angled chip slot to reduce manufacturing costs and improve sidewall strength.
    • Expectation of Success: The combination involved applying a known technique (chip removal slots) from Starbuck to a similar device (Redford's hole saw) to achieve a predictable result (improved cutting efficiency), leading to a high expectation of success.

Ground 3: Obviousness of Claims 1-21, 23-35, and 37 over Singh in view of Redford

  • Prior Art Relied Upon: Singh (Application # 2009/0035082) and Redford (Patent 7,237,291).

  • Core Argument for this Ground:

    • Prior Art Mapping: Singh disclosed a hole saw with multiple, separate slots positioned at different axial and circumferential locations to facilitate slug removal with a screwdriver. However, Singh required removing the screwdriver to move between slots. Redford taught a single, continuous S-shaped aperture that allows a pin to be moved between different axial positions without being removed from the hole saw. Petitioner argued that combining these references would result in a hole saw with multiple fulcrums (from Singh) connected by a continuous slot (from Redford).
    • Motivation to Combine: A POSITA would combine Singh and Redford to improve the functionality and convenience of Singh's design. Redford provided the motivation to connect Singh’s separate, spaced-apart slots with a continuous aperture. This modification would allow a user to move a prying tool between different fulcrum points without having to completely remove and reinsert it, making slug removal faster and easier.
    • Expectation of Success: A POSITA would have a reasonable expectation of success because the combination involved modifying a known device (Singh) with a known feature (Redford's continuous slot) to achieve the predictable benefit of easier tool manipulation. The petition asserted that this combination would inherently create a third fulcrum between the two original slot locations.

  • Additional Grounds: Petitioner asserted an alternative obviousness challenge (Ground 2) against claims 1-5, 14-20, 23-28, 30-34, and 37 over Redford alone. This ground argued that even if Redford did not anticipate the claims due to constructions of "hole cutter" or "configured to," it would have been obvious to use Redford's removable "cleaning flange" as a conventional hole saw for its known purpose.

4. Key Claim Construction Positions

"configured to receive... a lever" and similar functional language

Petitioner argued that this and similar phrases throughout the claims constituted functional, intended-use language that should not be given patentable weight. The proper analysis, per Petitioner, must focus on whether the prior art structure is capable of performing the recited function, not whether the prior art explicitly describes it for that purpose. This position was critical to the anticipation argument over Redford, which did not explicitly describe its S-shaped channel for slug removal but was allegedly capable of it.

"fulcrum"

Petitioner proposed the broadest reasonable interpretation of "fulcrum" as simply a support (e.g., a surface or edge of an aperture) on which a lever can be turned by a user. This construction did not require a lever to be present or constantly turning on the support for it to qualify as a fulcrum.

"means... for engaging the lever" (Claim 24)

Petitioner argued that the "first means," "second means," and "third means" in claim 24 were means-plus-function elements under 35 U.S.C. §112, sixth paragraph. The corresponding structure was identified in the specification as the fulcrums defined by the edges of the apertures.

5. Relief Requested

  • Petitioner requested institution of an inter partes review and cancellation of claims 1-37 of the ’554 patent as unpatentable.