PTAB

IPR2019-00380

Bowtech Inc v. MCP IP LLC

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Key Events
Petition
petition

1. Case Identification

2. Patent Overview

  • Title: Balanced Pulley Assembly for Compound Archery Bows, and Bows Incorporating That Assembly
  • Brief Description: The ’281 patent discloses a pulley assembly for a compound archery bow that includes a "cable controller" on at least one pulley. This controller is designed to modify the bow's operation by altering the force/draw profile to store more energy and to make the pulley system inherently self-balancing.

3. Grounds for Unpatentability

Ground 1: Obviousness over Mitchell and McPherson - Claims 1-2, 5-6, 8-10, and 12-21 are obvious over Mitchell in view of McPherson.

  • Prior Art Relied Upon: Mitchell (Patent 5,390,655) and McPherson (Patent 6,247,466).
  • Core Argument for this Ground:
    • Prior Art Mapping: Petitioner argued that the combination of Mitchell and McPherson taught all limitations of the challenged claims. Mitchell disclosed the foundational elements of a dual-cam compound bow, including a handle, limbs, and a pair of pulleys, each with grooves for a bowstring and cables. However, Mitchell's design, which anchored the cables to a simple mounting bracket on the opposing pulley's axle, lacked the claimed "cable controller." McPherson disclosed the missing element: a "secondary string feed-out" that functions identically to the ’281 patent's claimed cable controller. McPherson’s controller was independently and rotatably mounted on the cam at a pivot point offset from the main axle. This specific offset arrangement was McPherson's self-described "key feature," causing the cable to be initially taken up and then let out during the draw cycle—the very function recited in independent claims 1, 10, 15, and 19 of the ’281 patent. Petitioner contended that substituting McPherson's advanced cable controller for Mitchell's simple mounting bracket would result in the claimed invention. For dependent claims, Petitioner argued that features like a "pivotable member" or a grooved, circular "rotatable collar" were disclosed by the rotatable, pulley-shaped bosses in Mitchell, which were used to attach the forked ends of the bow cables.
    • Motivation to Combine: Petitioner asserted two primary motivations for a person of ordinary skill in the art (POSITA) to combine the references. First, a POSITA would combine them to achieve an improved force-draw profile and increase the energy stored in the bow. McPherson explicitly taught that its offset cable controller created a "take-up" effect during the initial draw, which increased energy storage potential. A POSITA would have been motivated to apply this known performance-enhancing component to a standard dual-cam bow like Mitchell's. Second, a POSITA would combine the references to introduce self-balancing features and improve tunability. Petitioner argued that dual-cam systems like Mitchell's, where cables are anchored to the opposing axle, were notoriously difficult to synchronize. A POSITA would have recognized that replacing this rigid connection with McPherson’s independently rotating controllers would improve synchronization and reduce maintenance, addressing a well-known problem in the art.
    • Expectation of Success: Petitioner argued that a POSITA would have had a reasonable expectation of success because incorporating McPherson's controller into Mitchell's bow was a simple substitution of one component for another to achieve a predictable improvement. The function of McPherson's controller was well-defined, and applying it to a standard dual-cam platform would predictably yield the benefits of an improved force-draw profile and better synchronization.

4. Key Claim Construction Positions

  • "rotatable collar": Petitioner proposed this term, found in multiple dependent claims, should be construed as "a component that collars a rotation axis, is capable of receiving a bow cable or string, and is capable of rotating." This construction was based on the specification's description of a "controller 52" configured as such. Petitioner asserted this construction was important to show that the rotatable, grooved "bosses" taught in Mitchell for attaching cable ends met the claim limitation, thereby rendering several dependent claims obvious.

5. Relief Requested

  • Petitioner requests institution of an inter partes review (IPR) and cancellation of claims 1-2, 5-6, 8-10, and 12-21 of the ’281 patent as unpatentable.