Mako Surgical Corp v. Carnegie Mellon University

1. Case Identification

• Case #: IPR2015-00630
• Patent #: 6,205,411
• Filed: January 28, 2015
• Petitioner(s): Mako Surgical Corp.
• Patent Owner(s): Blue Belt Technologies, Inc.
• Challenged Claims: 1-17

2. Patent Overview

• Title: Computer-Assisted Surgery Planner and Intra-Operative Guidance System
• Brief Description: The ’411 patent discloses systems and methods for planning and guiding the implantation of an artificial component into a joint. The invention combines a pre-operative geometric planner to create models of the joint and implant with a pre-operative kinematic biomechanical simulator to analyze joint movement and determine optimal implant positioning.

3. Grounds for Unpatentability

Ground 1: Obviousness over DiGioia in view of DiGioia II - Claims 1-17 are obvious over DiGioia in view of DiGioia II.

• Prior Art Relied Upon: DiGioia (a 1996 symposium article titled “HipNav: Pre-operative Planning and Intra-operative Navigational Guidance...”) and DiGioia II (a 1995 symposium article titled “An Integrated Approach to Medical Robotics and Computer Assisted Surgery...”).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that DiGioia, a publication by several of the ’411 patent’s inventors, disclosed nearly every element of the challenged claims more than one year before the patent’s effective filing date. The DiGioia reference described a “HipNav” system featuring a pre-operative geometric planner that uses CT images, a range of motion simulator that provides feedback to determine optimal implant placement, and an intra-operative tracking and guidance system (using an “Optotrak” camera) to accurately place the implant. This system was argued to teach the core limitations of independent claims 1 (apparatus), 10 (system), and 17 (method), including creating 3D bone and component models, simulating movement, and using tracking data for alignment. For claim 16, which requires a robotic device, Petitioner asserted this was an obvious addition based on DiGioia II.
  • Motivation to Combine (for §103 grounds): A person of ordinary skill in the art (POSITA) would combine the robotic surgery teachings of DiGioia II with the HipNav system of DiGioia. The motivation was exceptionally strong because both articles were written by the same research group, addressed the same technical problem of improving surgical accuracy, and were published only a year apart. DiGioia II explicitly proposed integrating pre-operative planning with computer or robot-assisted surgery, providing a clear roadmap for the combination.
  • Expectation of Success (for §103 grounds): A POSITA would have had a high expectation of success in combining the references, as they represented a well-documented and logical progression of the inventors’ own research into integrated surgical systems.
  • Key Aspects: Petitioner contended that the ’411 patent was not entitled to the 1997 priority date of its parent application. It argued that adding a specific list of joints (knee, shoulder, etc.) beyond the parent’s general disclosure of “joint” and specific disclosure of “hip joint” constituted new matter, limiting the challenged claims to the 1998 filing date. This rendered the 1995 and 1996 DiGioia references undisputedly prior art under 35 U.S.C. §102(b).

Ground 2: Obviousness over DiGioia II in view of Chao, O'Toole, and Taylor - Claims 1-17 are obvious over DiGioia II in view of multiple references.

• Prior Art Relied Upon: DiGioia II (a 1995 symposium article), Chao (a 1993 ASME journal article), O’Toole (a 1995 computer science article), and Taylor (a 1994 IEEE journal article).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that DiGioia II, published in 1995, disclosed the foundational computer system with a pre-operative geometric planner ("3-D Templating") communicating with a biomechanical simulator to provide feedback on an implant's position. This primary reference was argued to teach the core system architecture. The remaining limitations were obvious additions from other well-known prior art. Petitioner also asserted that claims 1-2 and 4-8 were anticipated by DiGioia II alone under 35 U.S.C. §102(b).
  • Motivation to Combine (for §103 grounds):
    • A POSITA would combine DiGioia II with Chao to add the explicit step of calculating a range of motion. While DiGioia II disclosed biomechanical simulation, Chao taught using such simulations specifically for planning joint replacements by analyzing joint motion, making it a natural and predictable improvement.
    • A POSITA would combine DiGioia II with O'Toole to add the required tracking device and intra-operative navigation. O'Toole, co-authored by many of the same inventors as DiGioia II, described using high-speed tracking with a robotic system to compensate for bone motion during surgery. Combining these complementary technologies from the same research team was presented as a simple design choice.
    • A POSITA would combine DiGioia II with Taylor to implement a specific type of tracking system. Taylor was a widely known article that disclosed an "Optotrak" camera-based 3D digitizer for orthopedic surgery, representing a known and available solution for the tracking element required by the system.
  • Expectation of Success (for §103 grounds): Success was expected because the combination involved integrating known, complementary components from the same technical field to create the claimed system. The shared authorship between DiGioia II and O'Toole further demonstrated the predictability of combining their respective teachings.

4. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-17 of the ’411 patent as unpatentable.