Align Technology Inc v. 3Shape AS

1. Case Identification

• Case #: IPR2020-01087
• Patent #: 10,349,042
• Filed: June 18, 2020
• Petitioner(s): Align Technology, Inc.
• Patent Owner(s): 3Shape As
• Challenged Claims: 1-22

2. Patent Overview

• Title: Intraoral Focus Scanner with Non-Telecentric Optics
• Brief Description: The ’042 patent describes an apparatus and method for optical 3D scanning of surfaces, particularly suited for intraoral applications like scanning teeth. The system uses confocal principles, projecting an illumination pattern onto an object, varying the focus plane, and evaluating a correlation measure to determine in-focus positions and construct a 3D model.

3. Grounds for Unpatentability

Ground 1: Obviousness of Claims 1-3, 6-8, 10, and 13-22 over Morgan and Geng

• Prior Art Relied Upon: Morgan (Patent 5,381,236) and Geng (Patent 7,099,732).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Morgan taught the core features of a confocal scanner, including a non-telecentric lens system for focusing patterned light, moving a lens to shift the focus plane, capturing 2D images, and determining in-focus positions based on contrast. However, Morgan did not expressly disclose an intraoral-specific scanner with a tip or a color image sensor. Geng was argued to supply these missing elements, teaching an intraoral imaging device with a tip for scanning dental structures and color imaging capabilities for creating dental appliances with accurate shading.
  • Motivation to Combine: Petitioner contended a person of ordinary skill in the art (POSA) would be motivated to combine these references. Since Morgan suggested its scanner for dental applications ("mapping dental cavities"), a POSA would have naturally looked to known intraoral scanning technologies like Geng to adapt it for that purpose. This would include adding a tip for insertion into the oral cavity. Furthermore, adding Geng's color-sensing capabilities would be a predictable improvement to create more aesthetically pleasing and "natural" looking dental restorations, such as the ceramic inserts mentioned by Morgan.
  • Expectation of Success: A POSA would have had a reasonable expectation of success. The components and principles for color imaging in intraoral scanners were well-known and routine. Geng demonstrated the successful integration of 3D and color imaging, providing a clear path for a POSA to incorporate its color-sensing features into Morgan's foundational confocal scanning system without undue experimentation.

Ground 2: Obviousness of Claims 1-3, 6-8, 10, and 13-22 over Noguchi

• Prior Art Relied Upon: Noguchi (Japanese Patent 3321866).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner asserted that Noguchi, by itself, rendered the challenged claims obvious. Noguchi taught a confocal scanner for detecting the 3D shape of objects and explicitly recognized its applicability to intraoral scanning ("perform observation and measurement of recessed areas inside the oral cavity"). The petition argued Noguchi disclosed all key claimed features: a non-telecentric optical system (addressing image distortions computationally), projecting a texture pattern, an image sensor, shifting the focus plane to capture multiple images, and a compact detection head with a tip suitable for intraoral use. Noguchi also expressly suggested using a color image sensor to capture images illuminated by different colors.
  • Motivation to Combine (Implicit): Although a single-reference ground, the motivation was inherent in Noguchi's own disclosure. Noguchi taught a base scanner in its Figure 11 and then, in Figure 16, taught a modification to include color-sensing capabilities. A POSA reading Noguchi would have understood that these features could and should be combined to create an improved intraoral scanner capable of capturing both 3D geometry and color information.
  • Expectation of Success: Success was expected because Noguchi described a complete and integrated system. It taught how to detect in-focus positions based on contrast changes and how to apply this to intraoral measurements, providing a full blueprint for the claimed invention.

• Additional Grounds: Petitioner asserted additional obviousness challenges, including:

  • Combining Morgan and Geng with Bayer (Patent 3,971,065) to teach the use of a Bayer filter array for the color image sensor (Claims 4-5, 9).
  • Combining Morgan and Geng with Englehardt (Patent 6,263,234) to teach the inclusion of the scanner components in a handheld unit that transmits data to a separate workstation (Claims 11-12).
  • Similar combinations based on Noguchi, adding Bayer for the Bayer filter array (Claims 4-5, 9) and Englehardt for the handheld unit configuration (Claims 11-12).

4. Key Claim Construction Positions

• "focus plane": Petitioner applied the patent’s explicit definition: "[a] surface where light rays emitted from the pattern converge to form an image on the object being scanned," noting it may be a curved surface. This construction was central to mapping the prior art's method of sweeping focus through an object's volume.
• "image measure": For claims 6-8, Petitioner noted that in related litigation, this term was found indefinite. However, for the IPR, Petitioner adopted the Patent Owner's broad litigation position that the term is not limited to the "correlation measure" in the specification but includes any measure of the image, such as light intensity or contrast, which is what prior art like Morgan taught.

5. Key Technical Contentions (Beyond Claim Construction)

• "Non-Telecentric" and Related Language: A central contention was that the convoluted language in independent claims 1 and 21 (e.g., "first divergence angle," "second propagation axis," "non-parallel") was not standard terminology but was merely the Patent Owner's attempt to describe a conventional non-telecentric optical system. Petitioner argued that any standard, non-telecentric lens arrangement, like those shown in Morgan and Noguchi, would inherently meet these limitations, as chief rays from different field points would necessarily travel along non-parallel paths and diverge relative to the optical axis.

6. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under Fintiv was unwarranted. The primary reasons given were: (1) Petitioner acted diligently, filing the IPR less than ten months after the ’042 patent was added to the parallel district court litigation via an amended complaint; (2) there was minimal investment in the litigation on this specific patent, as expert discovery had not occurred; (3) the scheduled trial date was speculative and likely to be delayed due to the COVID-19 pandemic; and (4) the IPR presented stronger, more focused invalidity grounds than the broader, preliminary contentions in the district court case. Petitioner also stipulated not to pursue in the district court any ground on which the Board institutes review.

7. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 1-22 of the ’042 patent as unpatentable.