3Shape AS v. Align Technology Inc

1. Case Identification

• Case #: IPR2020-00173
• Patent #: 8,102,538
• Filed: December 9, 2019
• Petitioner(s): 3Shape A/S and 3Shape Inc.
• Patent Owner(s): Align Technology, Inc.
• Challenged Claims: 1-4, 17-19

2. Patent Overview

• Title: Device for Determining Surface Topology and Associated Color of a 3D Structure
• Brief Description: The ’538 patent describes a device for determining the three-dimensional surface shape and associated color of an object, such as teeth. The device uses an "optical scanner" to provide depth data and a separate "imaging means" to provide two-dimensional color image data, which are then associated.

3. Grounds for Unpatentability

Ground 1: Obviousness over Okamoto and Xu - Claims 1-2 are obvious over Okamoto in view of Xu.

• Prior Art Relied Upon: Okamoto (Japanese Patent Publication No. 2001-82935) and Xu (Patent 5,912,735).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Okamoto disclosed a device with the core elements of claim 1: a confocal optical system for obtaining 3D depth data (the "optical scanner") and a separate, non-confocal system with a white light source and CCD for obtaining color data (the "imaging means"). However, Petitioner contended that Okamoto did not explicitly teach that the depth and color capture operations are substantially simultaneous. To supply this element, Petitioner cited Xu, which disclosed a laser imaging system providing both confocal depth data and a white light color image, and expressly taught the desirability of "contemporaneous, or substantially simultaneous laser/white light viewing" to create a combined image.
  • Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would combine Okamoto and Xu because both addressed the same technical problem of combining 3D surface topology with color data. Xu taught that simultaneous operation was desirable to reduce positional errors caused by mechanical vibrations or object movement, a well-known problem in scanning. A POSITA would therefore have been motivated to modify Okamoto's device with Xu's teaching of simultaneous acquisition to improve the accuracy and reliability of the combined data by reducing positional shifts between the depth and color scans.
  • Expectation of Success: A POSITA would have had a reasonable expectation of success in this combination. The modification involved applying a known technique (simultaneous scanning) from Xu to a similar system (Okamoto) to achieve a predictable result (reduced positional error). Xu provided a straightforward implementation using a holographic notch filter to separate the laser and white light signals, demonstrating a clear and feasible path for the combination.

Ground 2: Obviousness over Babayoff, Okamoto, and Xu - Claims 1-4 and 17-19 are obvious over Babayoff in view of Okamoto and Xu.

• Prior Art Relied Upon: Babayoff (WO 00/08415), Okamoto (Japanese Patent Publication No. 2001-82935), and Xu (Patent 5,912,735).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner asserted that Babayoff taught a handheld confocal scanning system for obtaining 3D depth data of teeth but did not disclose a means for capturing color data. Petitioner argued that Babayoff disclosed all elements of the "optical scanner" in claims 1-4, including the "probing member" of dependent claim 3. The teachings of Okamoto and Xu were then incorporated to supply the missing "imaging means" for color capture and the rationale for simultaneous operation, as detailed in Ground 1. The combination of all three references, therefore, was alleged to render claims 1-4 and 17-19 obvious.
  • Motivation to Combine: A POSITA would have been motivated to modify Babayoff's dental scanner to include a color imaging system as taught by Okamoto and Xu. The desirability of obtaining accurate color information for dental prostheses to match a patient's teeth was well-known in the art. Adding the color capture functionality of Okamoto/Xu to Babayoff's proven depth-scanning system would have been a natural and desirable improvement to enable more accurate orthodontic and prosthetic applications.
  • Expectation of Success: A POSITA would have had a high expectation of success because combining 3D scan data with 2D color images was a conventional technique for creating 3D models of teeth. The petition argued that processors capable of associating different data types were readily available and that incorporating them into a handheld device like Babayoff's was a matter of routine implementation, not invention. The similarities between the confocal systems in all three references would have made the integration straightforward.

4. Key Claim Construction Positions

• "optical scanner" (claims 1-4, 17-19): Petitioner argued this term should be construed under §112, ¶6 as a means-plus-function limitation. The proposed function was "providing depth data," and the corresponding structure was a "confocal optical system" as described in the specification. This construction is narrower than the Patent Owner's proposed plain-meaning construction and was central to mapping the prior art's confocal systems to the claims.
• "imaging means" (claims 1-4, 17-19): Similarly, Petitioner argued this term was a means-plus-function limitation for "providing two-dimensional color image data," with the corresponding structure being the white light illumination and sensor systems disclosed in the patent.
• "maintaining a spatial disposition...substantially fixed during operation..." (claims 1-4, 17-19): A key dispute existed over this clause. Petitioner argued it meant the device was fixed during the separate operations of the scanner and imager. In contrast, the Patent Owner and the Administrative Law Judge (ALJ) in a related ITC investigation construed it to mean the operations were simultaneous or effectively so. Petitioner's obviousness grounds were structured to succeed under either construction, using Xu to explicitly teach simultaneity.

5. Arguments Regarding Discretionary Denial

• Petitioner argued against discretionary denial under §314(a) and §325(d). It was asserted that the co-pending Delaware litigation and ITC investigation were in early stages with no validity determinations issued. Petitioner noted that the IPR challenged a broader set of claims (1-4, 17-19) than the ITC case (1-2), a factor weighing against denial. Further, it was argued that denial under §325(d) was improper because the primary references (Okamoto and Xu) presented in the petition were not considered or applied by the Examiner during the original prosecution of the '538 patent.

6. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-4 and 17-19 of the ’538 patent as unpatentable.