3Shape AS v. Align Technology Inc

1. Case Identification

• Case #: IPR2020-01642
• Patent #: 10,507,088
• Filed: September 22, 2020
• Petitioner(s): 3Shape A/S and 3Shape Inc.
• Patent Owner(s): Align Technology, Inc.
• Challenged Claims: 11-15, 17, 27, and 30

2. Patent Overview

• Title: Intraoral Imaging Apparatus and Method
• Brief Description: The ’088 patent relates to an intraoral imaging apparatus, such as a dental scanner, that operates without a field lens. The system uses a translation mechanism to move at least one lens along an optical path to displace a non-flat focal surface and includes methods for computationally compensating for distortions arising from this scanner design.

3. Grounds for Unpatentability

Ground 1: Obviousness over Berner and Ginani - Claims 11-15, 17, 27, and 30 are obvious over Berner in view of Ginani under 35 U.S.C. §103.

• Prior Art Relied Upon: Berner (Application # 2010/0085636) and Ginani (an Optical Scanning Sensor System with Submicron Resolution dissertation (2013)).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Berner discloses a confocal optical system for intraoral scanning that meets most limitations of independent claims 11 and 27. Specifically, Petitioner asserted Berner taught an apparatus lacking a field lens, using a movable lens (lens 4) to adjust focus, which results in a non-flat (curved) focal surface, and computationally compensating for the resulting image distortions. Petitioner contended the key element missing from Berner was an "illumination module" for generating a "plurality of light beams" as required by the claims. The Ginani reference, a dissertation on optical scanning systems, was introduced to supply this teaching. Ginani described using a microlens array in a confocal system to create multiple parallel light beams, a known technique for parallel scanning used to increase the field of view and scanning speed. Petitioner argued that combining Ginani’s microlens array with Berner's system would result in the claimed invention.
  • Motivation to Combine: A person of ordinary skill in the art (POSITA) would combine Berner and Ginani because both references address the design of compact confocal scanners and share the objective of providing a smaller, efficient scanning device. Petitioner asserted a POSITA would be motivated to use Ginani’s microlens array to solve the known problem of scanning large, immovable objects (like teeth) by enabling parallel scanning, a technique Berner itself contemplated by referencing other prior art that used microlens arrays. The petition framed the combination as a predictable application of known techniques to improve a known device, not an inventive leap.
  • Expectation of Success: Petitioner argued a POSITA would have a reasonable expectation of success in making the combination. Integrating a standard component like Ginani's microlens array into Berner's confocal system would involve routine, well-established optical design methods. Because both systems operated on similar confocal principles and addressed correcting for optical distortions, a POSITA would expect the combined system to function predictably and maintain the high image quality needed for accurate 3D surface geometry, as described in Berner.

4. Key Claim Construction Positions

• "a translation mechanism..." (claim 11): Petitioner argued this phrase should be construed under §112(f) as a means-plus-function term. The recited function is "to adjust a location of at least one lens of the plurality of lenses to displace the focal surface along an imaging axis defined by the optical path." The corresponding structure disclosed in the ’088 patent specification to perform this function is motor 72.
• "detected positions... are to be adjusted to compensate..." (claims 11 and 27): Petitioner proposed this phrase should be interpreted to mean that adjustments are made to the captured image information (i.e., the raw scan data) prior to the generation of a final three-dimensional model of the scanned object.
• "an illumination module..." (claim 15): Petitioner argued this phrase should also be construed under §112(f) as a means-plus-function term. The recited function is "to generate an array of light in an x-y plane," with the corresponding structure disclosed in the specification being a grating, microlens array, optics expander, or equivalents thereof.

5. Key Technical Contentions (Beyond Claim Construction)

• A central technical argument concerned claim 17, which requires "a radius of a largest lens of the plurality of lenses is less than 13 millimeters." Petitioner argued that while Berner does not explicitly state this dimension, it can be derived from its Figure 2. By using a stated thickness of 31.5 mm for certain optical components in Berner to establish a pixel-to-millimeter ratio (14.35 pixels/mm), Petitioner calculated the diameter of the largest lens (lens 4) in Berner's figure to be approximately 18.5 mm. This corresponds to a radius of 9.3 mm, which meets the claimed limitation. Alternatively, Petitioner argued that it would have been obvious for a POSITA to scale down the system for a compact intraoral application, which would inevitably satisfy the dimensional requirement.

6. Arguments Regarding Discretionary Denial

• Petitioner argued against discretionary denial of institution under §314(a) based on the Fintiv factors. They asserted that the parallel district court litigation was in its early stages with an uncertain trial date, minimizing the risk of significant overlap or duplicative efforts. The petition highlighted that key milestones like expert discovery cutoff (May 2021) were scheduled well after the anticipated institution decision (March 2021). Petitioner also stipulated that it would not pursue the same invalidity ground in court if the inter partes review (IPR) was instituted and contended that the strong merits of the petition weighed heavily in favor of institution.
• Petitioner also argued against denial under §325(d), which addresses art previously presented to the PTO. They contended that the primary prior art reference, Berner, was never substantively considered by the Examiner during prosecution, despite being listed on an Information Disclosure Statement. Petitioner asserted the Examiner materially erred by not applying Berner, as it explicitly discloses the key limitations (compensation for a non-flat focal surface and for the absence of a field lens) that the Examiner had relied upon as the basis for allowing the patent claims.

7. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 11-15, 17, 27, and 30 of Patent 10,507,088 as unpatentable.