3Shape AS v. Align Technology Inc

1. Case Identification

• Case #: IPR2021-01240
• Patent #: 10,709,527
• Filed: July 19, 2021
• Petitioner(s): 3Shape A/S and 3Shape Inc.
• Patent Owner(s): Align Technology, Inc.
• Challenged Claims: 1-9, 11-20, and 22

2. Patent Overview

• Title: Method and System for Manipulating Virtual Dental Models
• Brief Description: The ’527 patent describes methods and systems for intraoral 3D scanning to create a virtual dental model. The technology addresses instances where parts of the intraoral structure are obstructed (e.g., by gums or saliva), resulting in a virtual model with missing portions, by generating additional data to fill in these gaps.

3. Grounds for Unpatentability

Ground I: Obviousness over Rubbert and Weyrich - Claims 1, 4-9, 11, 12, 15-20, and 22 are obvious over Rubbert in view of Weyrich.

• Prior Art Relied Upon: Rubbert (Application # 2002/0180760) and Weyrich (a 2004 Eurographics Symposium paper).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Rubbert disclosed a method for creating a 3D virtual model of a patient’s dentition using a hand-held intraoral scanner. Rubbert acknowledged that these scanned models could have missing data or holes due to obstructions or scanning geometries. Weyrich was presented as addressing this exact problem, teaching a comprehensive set of user-guided tools to process corrupted 3D scan data, including "spray can" and automatic hole-filling tools to repair missing portions in a 3D point cloud.
  • Motivation to Combine: Petitioner contended a POSITA would combine Weyrich’s error-correction tools with Rubbert’s dental modeling system to solve the known problem of gaps in the scan data identified by Rubbert. Applying Weyrich’s known techniques to Rubbert's system would predictably improve the accuracy and completeness of the dental models, providing a more robust user interface for correcting scan data errors.
  • Expectation of Success: A POSITA would have had a high expectation of success because both references operate on the same type of data (3D point clouds from optical scanners) to solve the same problem (holes or missing data). Weyrich’s tools were based on fundamental and well-known graphics concepts, making their implementation straightforward.

Ground II: Obviousness over Rubbert, Weyrich, and Babayoff - Claims 2, 3, 13, and 14 are obvious over Rubbert and Weyrich in further view of Babayoff.

• Prior Art Relied Upon: Rubbert (Application # 2002/0180760), Weyrich (a 2004 Eurographics Symposium paper), and Babayoff (WO 00/08415).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground built upon Ground I, adding Babayoff to address dependent claims reciting a scanner that uses an "array of light beams" and "confocal focusing." Petitioner asserted that Babayoff explicitly disclosed a hand-held intraoral scanner with these exact features. The ’527 patent itself incorporated Babayoff by reference for disclosing a suitable scanner.
  • Motivation to Combine: The motivation was characterized as a simple substitution of a known component for an improved one to achieve predictable benefits. A POSITA would replace the scanner in the Rubbert/Weyrich combination with Babayoff’s confocal scanner to gain advantages taught by Babayoff, such as improved accuracy, reduced scanning time, and eliminating the need for a reflective coating on the teeth, which was sometimes required by conventional scanners like Rubbert's.

Ground III: Obviousness over Durbin, Weyrich, and Babayoff - Claims 1-9, 11-20, and 22 are obvious over Durbin in view of Weyrich and Babayoff.

• Prior Art Relied Upon: Durbin (Application # 2002/0064759), Weyrich (a 2004 Eurographics Symposium paper), and Babayoff (WO 00/08415).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground substituted Durbin for Rubbert as the primary reference. Petitioner argued Durbin disclosed a system for creating a digital dental model from intraoral scans and taught assessing the model's quality by highlighting "anomalous regions" for a user to "resolve as appropriate." However, Durbin did not specify how the user should resolve these anomalies. Weyrich provided the missing element by teaching the specific user-guided tools (e.g., eraser, hole-filling) to correct such errors. Babayoff was again used to supply the confocal scanner limitations.
  • Motivation to Combine: Petitioner asserted Durbin provided an explicit motivation to seek out Weyrich’s teachings. By identifying a problem (anomalous data requiring user resolution) without providing a specific toolset, Durbin would have prompted a POSITA to look for known techniques for manipulating 3D models. Weyrich provided a known, suitable, and readily implementable solution. The motivation to incorporate Babayoff’s scanner was the same as in Ground II: substitution for a superior component with known benefits.
  • Expectation of Success: Success was expected because Durbin identified errors early in the data processing pipeline on a "3D representation of the digital model," which is precisely the stage at which Weyrich’s point-cloud-based correction tools are designed to operate.

4. Arguments Regarding Discretionary Denial

• §314(a) (Fintiv Factors): Petitioner argued against discretionary denial, stating the parallel district court litigation was in its early stages with no trial date set, which would likely be more than two years away. Petitioner highlighted the significant non-overlap between the twenty claims challenged in the IPR and the five claims asserted in litigation. Furthermore, Petitioner stipulated that if the IPR were instituted, it would not pursue the same invalidity grounds in the district court, thus preventing duplicative efforts.
• §325(d): Petitioner contended that denial under §325(d) was inappropriate because the core prior art and asserted combinations were never considered by the USPTO during prosecution. The patent issued after a first-action allowance with only a cursory, non-substantive reference to a related Rubbert application in the Notice of Allowance. The primary references of Durbin and Weyrich were not before the examiner at all, meaning the current arguments were materially different from those considered during prosecution.

5. Relief Requested

• Petitioner requested the institution of an inter partes review and the cancellation of claims 1-9, 11-20, and 22 of the ’527 patent as unpatentable.