Align Technology, Inc. v. 3Shape A/S

1. Case Identification

• Case #: PGR2018-00104
• Patent #: 9,962,244
• Filed: October 26, 2018
• Petitioner(s): Align Technology, Inc.
• Patent Owner(s): 3SHAPE A/S
• Challenged Claims: 31, 32, 34

2. Patent Overview

• Title: 3D Scanning of Surface Geometry and Color
• Brief Description: The ’244 patent relates to a system and method for three-dimensional (3D) scanning of objects, particularly for intraoral dental scanning, to record both surface geometry and surface color. The technology uses a focus scanner with a multichromatic light source to capture a series of 2D images at different focal planes, which are then processed by a data system to generate a 3D representation of the object.

3. Grounds for Unpatentability

Ground 1: Obviousness over Fisker and Tanaka - Claims 31 and 32 are obvious over Fisker in view of Tanaka.

• Prior Art Relied Upon: Fisker (Application # 2012/0092461) and Tanaka (Application # 2015/0029367).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Fisker taught a handheld 3D focus scanner for obtaining surface geometry and color using a multichromatic light source, a color image sensor, and a data processing system that captures a stack of 2D images at different focus planes, mapping to most limitations of claim 31. However, Fisker allegedly did not explicitly teach claim limitations related to specific color filter array (CFA) arrangements, such as the proportion of pixels matching a selected wavelength being larger than 50% or the specific 6x6 cell arrangement in claim 32. Petitioner asserted that Tanaka disclosed these missing elements, teaching a CFA with a proportion of green filters greater than 50% (20 of 36) and a specific 6x6 pixel array to improve image quality.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Tanaka's improved CFA with Fisker’s scanner to achieve the known goals of improving image resolution and suppressing the generation of false color. Because Fisker’s system was aimed at improving spatial resolution, a POSITA would have been motivated to incorporate Tanaka’s known CFA pattern to enhance image quality.
  • Expectation of Success: A POSITA would have had a reasonable expectation of success, as the modification involved combining a known filter scheme into a known type of scanner to achieve the predictable benefit of improved image accuracy.

Ground 2: Obviousness over Fisker, Suzuki, and Cai - Claim 34 is obvious over Fisker in view of Suzuki or Cai.

• Prior Art Relied Upon: Fisker (Application # 2012/0092461), Suzuki (Application # 2013/0070128), and Cai (Application # 2010/0067789).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that claim 34 adds limitations to claim 31 concerning the data processing steps, including calculating a correlation measure and computing an averaged sub-scan color. Petitioner argued Fisker taught deriving geometry and color by calculating a correlation measure between an image portion and a weight function to find a maximum value. For the limitation of "computing an averaged sub-scan color," which Fisker did not explicitly teach, Petitioner pointed to Suzuki and Cai. Suzuki taught a method for correcting defective pixels using a weighted average of surrounding pixels, and Cai taught a method for obtaining an interpolated color value by averaging adjacent pixels of the same color.
  • Motivation to Combine: A POSITA would combine the pixel averaging techniques of Suzuki or Cai with Fisker's system to improve the accuracy of color data. Since Fisker was concerned with image quality, a POSITA would have recognized the benefit of including known methods for correcting or interpolating color values to produce a more accurate final 3D model.
  • Expectation of Success: The combination was a routine matter of implementing known software algorithms for pixel averaging into Fisker's data processing system, which would not require new hardware and would predictably result in enhanced color accuracy.

Ground 3: Obviousness over Thiel, Thiel, and Tanaka - Claims 31 and 32 are obvious over Thiel425 and Thiel576 in view of Tanaka.

• Prior Art Relied Upon: Thiel425 (Application # 2012/0075425), Thiel576 (Application # 2011/0080576), and Tanaka (Application # 2015/0029367).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that Thiel425 and Thiel576, which share an inventor and were filed closely in time, collectively taught a handheld dental focus scanner for performing 3D measurements. Thiel425 focused on capturing surface geometry from a stack of 2D images, while Thiel576 taught determining an object's surface color. Petitioner asserted their combination taught a scanner for recording both geometry and color. As with the Fisker-based ground, Petitioner relied on Tanaka to supply the specific CFA limitations, including the >50% proportion of pixels for a selected wavelength and the specific 6x6 cell arrangement.
  • Motivation to Combine: A POSITA would have naturally considered the two Thiel references together given their common inventor, assignee, and complementary subject matter. A POSITA would then be motivated to incorporate Tanaka's known CFA pattern into the Thiel scanner to enhance image resolution and reduce false color, a well-understood goal in the field.
  • Expectation of Success: The combination involved enhancing a known scanner with a known component for the predictable purpose of improving image quality, which a POSITA could implement with a reasonable expectation of success.

• Additional Grounds: Petitioner asserted additional obviousness challenges against claim 34 based on combinations of Thiel425, Thiel576, Fisker, Suzuki, and Cai, relying on similar rationales of combining primary scanner systems with secondary art teaching specific data processing techniques.

4. Key Technical Contentions (Beyond Claim Construction)

• PGR Eligibility: Petitioner contended that the ’244 patent was eligible for Post-Grant Review (PGR) because at least claims 19, 25, and 32 lacked written description support in the priority provisional application. Petitioner argued that the provisional's disclosure of an "alternative color filter array" in its Figure 4 was insufficient to support the specific claim limitations regarding the x,y positions of color filters in a 6x6 cell (claims 19 and 32) and specific pixel proportions (claim 25). Without this support, the effective filing date for these claims was post-AIA, making the patent subject to PGR.

5. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under 35 U.S.C. § 325(d) would be inappropriate. The core argument was that while the Examiner considered the primary reference Fisker during prosecution, the allowance was based on dependent claim limitations for which the Examiner did not consider the newly cited secondary art (e.g., Tanaka, Suzuki, Cai). Petitioner asserted the Examiner performed a limited search and did not have the benefit of the specific combinations and arguments presented in the petition. Therefore, the petition raised issues not substantively considered by the Office, and the new art was not cumulative, weighing in favor of institution.

6. Relief Requested

• Petitioner requests institution of post-grant review and cancellation of claims 31, 32, and 34 of the ’244 patent as unpatentable.