PTAB

IPR2024-00835

GodberSen Smith CoNSTructION Co v. Guntert & Zimmerman CoNST Div Inc

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1. Case Identification

2. Patent Overview

  • Title: Swing Leg Assembly for Concrete Paver
  • Brief Description: The ’318 patent relates to a swing leg assembly for a slipform concrete paver. The purported invention is a sensor-based control system designed to coordinate the pivoting of a swing leg with the rotation of an attached crawler track, ensuring the track remains oriented in the paving direction.

3. Grounds for Unpatentability

Ground 1: Claims 1-8 are obvious over CIII and Rio.

  • Prior Art Relied Upon: CIII (Commander III New Generation Trimmer/Paver Operator/Service Manual) and Rio (Patent 7,523,995).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that CIII, a manual for a commercial slipform paver, discloses all basic mechanical elements of the claimed swing leg assembly, including the paver frame, a pivoting swing leg, a jacking column, and a rotatable crawler track. However, CIII’s system required manual adjustment. Petitioner asserted that Rio, a patent for a road-milling machine, teaches the claimed automated control system. Specifically, Rio discloses a slew drive (a worm-gear rotary actuator) to rotate the track, a first sensor to detect the swing leg's angular position, and a second sensor to detect the track's rotational angle. Petitioner contended that combining these references provides the processor logic recited in claim 1[G]: receiving signals from both sensors and sending a control signal to the slew drive to automatically adjust the track's orientation in response to swing leg movement.
    • Motivation to Combine: A POSITA would combine Rio’s automated control system with CIII’s paver to replace CIII's manual, time-consuming, and error-prone adjustment process. The combination would yield predictable benefits, including improved maneuverability, operational efficiency, and safety by eliminating manual intervention and replacing a bulky steering linkage with Rio’s compact rotary actuator.
    • Expectation of Success: Petitioner asserted a high expectation of success because both references are in the analogous art of heavy road-construction machinery. The combination involves substituting one known steering and control method for another to achieve the predictable result of automation, a well-established engineering practice.

Ground 2: Claims 2-7 are obvious over CIII, Rio, and Smolders.

  • Prior Art Relied Upon: CIII, Rio (Patent 7,523,995), and Smolders (Patent 6,481,924).
  • Core Argument for this Ground:
    • Prior Art Mapping: This ground builds on Ground 1 and adds Smolders to further support the obviousness of dependent claims 2-7. For claim 2, which adds a "hinge bracket" between the swing leg and the paver frame, Petitioner argued that CIII already discloses such a bracket in its three-track configuration. Smolders, another slip-form paver patent, was introduced to show the conventionality of using hinge brackets on multiple swing leg assemblies. The remaining dependent claims (3-7)—reciting features like a hydraulic actuator on the hinge, disengagement for transport, and sensor positioning—were argued to be obvious implementations based on the collective teachings of CIII and Rio.
    • Motivation to Combine: A POSITA would be motivated to add the hinge bracket taught by CIII and Smolders to all swing legs of the modified CIII-Rio paver to facilitate easy assembly and disassembly. This improves maintenance, allows for greater flexibility in paving configurations, and reduces manufacturing costs by enabling the use of common parts across different machine setups.
    • Expectation of Success: Success would be expected, as it is a simple combination of familiar mechanical elements (hinge brackets, actuators) used for their intended purpose in a known application, as demonstrated by the prior art.

4. Key Claim Construction Positions

  • Petitioner contended that the claims do not require "on-the-fly steering" (i.e., rotating the crawler track while it is in contact with the ground). It was argued that the claims should encompass embodiments where the track is lifted before rotation, a position the Petitioner asserted was adopted by the Board in the Final Written Decision (FWD) for the related ’749 patent.

5. Key Technical Contentions (Beyond Claim Construction)

  • A central contention was that the CIII manual qualifies as a prior art "printed publication" under 35 U.S.C. §102. Petitioner provided substantial evidence, including a manager's declaration and extensive distribution records, to demonstrate that over 100 copies of the manual were distributed to customers and dealers without restriction or confidentiality obligations well before the patent's earliest priority date.

6. Arguments Regarding Discretionary Denial

  • Petitioner argued that discretionary denial under §325(d) would be inappropriate. While the asserted prior art references were submitted to the USPTO during prosecution via an Information Disclosure Statement (IDS), Petitioner contended the Examiner never substantively reviewed them or provided any analysis explaining why the claims were allowable over them. The petition asserted that the applicant failed to highlight the significance of the art or the Board’s adverse FWDs in related cases, and this lack of substantive examination constitutes a material error by the Office that warrants the Board's reconsideration of the art.

7. Relief Requested

  • Petitioner requests institution of an IPR and cancellation of claims 1-8 of Patent 11,535,318 as unpatentable.