ClearCorrect Operating LLC v. Align Technology Inc

1. Case Identification

• Case #: IPR2025-00820
• Patent #: 11,648,090
• Filed: April 14, 2025
• Petitioner(s): ClearCorrect Operating, LLC
• Patent Owner(s): Align Technology, Inc.
• Challenged Claims: 1-11

2. Patent Overview

• Title: Method of Making Multilayer Dental Aligner
• Brief Description: The ’090 patent discloses methods for making multilayer dental aligners from polymer sheets. The claims recite a method using a multilayer sheet with at least a first co-polyester layer, a second thermoplastic polyurethane (TPU) layer, and a third layer, with the layers defined by specific mechanical properties.

3. Grounds for Unpatentability

Ground 1: Claims 1-2, 4-5, and 8-11 are obvious over Tadros in view of Porter, Kalili, and Texin 990R.

• Prior Art Relied Upon: Tadros (Application # 2005/0100853), Porter (a 2007 article in Plastics Technology), Kalili (Application # 2011/0020761), and Texin 990R (a 2002 product datasheet).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Tadros disclosed the basic claimed structure: a three-layer "soft-hard-soft" dental aligner with a hard middle layer (polycarbonate-copolyester mixture) and soft outer layers (polyurethanes). To meet the specific material property limitations, Petitioner pointed to Porter, which disclosed a BPA-free Tritan co-polyester with the claimed properties for the hard co-polyester layer, and to Kalili and the Texin 990R datasheet, which together disclosed a specific TPU (TEXIN 990R) having the claimed properties for the soft TPU layer.
  • Motivation to Combine: A POSITA would combine the references to improve upon Tadros's design. The motivation was to replace Tadros's polycarbonate-containing hard layer with Porter's safer (BPA-free) and better-performing (improved thermoforming) Tritan co-polyester. A POSITA would also use the specific TEXIN 990R TPU disclosed in Kalili for the soft layers in Tadros's aligner because Kalili taught its "outstanding" properties for the identical application.
  • Expectation of Success: Petitioner asserted a POSITA would have an expectation of success because Tritan was a known industrial replacement for polycarbonate, and TEXIN 990R was known to be highly suitable for dental aligners. Furthermore, known manufacturing techniques like adhesive lamination would preserve the individual polymer properties within the multilayer structure.

Ground 2: Claims 1-11 are obvious over Tadros, Porter, Kalili, and Texin 990R, and further in view of Wen.

• Prior Art Relied Upon: The combination from Ground 1, with the addition of Wen (International Publication No. WO 2006/096558).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground incorporated the combination from Ground 1 and added the teachings of Wen to address the remaining dependent claims (3, 6, 7) related to a four-layer structure. Petitioner argued Wen taught the advantages of replacing a single thick polymer layer with multiple thinner sublayers of the same material. This known technique improved thermoforming and enhanced bonding between layers of disparate materials.
  • Motivation to Combine: A POSITA would combine Wen with the prior art from Ground 1 to further improve the aligner's performance. Specifically, a POSITA would apply Wen's teaching to subdivide the single hard Tritan layer (from the Ground 1 combination) into two thinner hard layers. This modification would result in a "soft-hard-hard-soft" structure, directly mapping onto the limitations of claims 3, 6, and 7.
  • Expectation of Success: Success was expected because subdividing layers was a predictable and common technique in polymer thermoforming used to achieve the well-understood benefits of better conformity and interlayer bonding.

Ground 3: Claims 1-6 and 8-11 are obvious over Kalili in view of Porter, Wen, and Texin 990R.

• Prior Art Relied Upon: Kalili (Application # 2011/0020761), Porter (a 2007 article), Wen (WO 2006/096558), and Texin 990R (a 2002 product datasheet).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground used Kalili's two-layer "soft-hard" aligner (soft TPU inner layer, hard polycarbonate outer layer) as the base reference. As in other grounds, Porter provided the Tritan co-polyester with the claimed hard layer properties as a replacement for Kalili's polycarbonate, and Texin 990R provided the data for Kalili's soft TPU layer. Wen's teaching of subdividing a single layer into thinner sublayers was then applied to the hard Tritan layer.
  • Motivation to Combine: The motivation was to make a series of known improvements to Kalili's base design. First, a POSITA would replace Kalili's polycarbonate with Porter's safer and higher-performance Tritan. Second, to improve manufacturing and fit, a POSITA would apply Wen's teaching to split the single hard Tritan layer into two thinner layers. This process would result in a three-layer "soft-hard-hard" configuration meeting the limitations of the challenged claims.
  • Expectation of Success: A POSITA would have expected success because the combination involved substituting known materials for known benefits (Tritan for polycarbonate) and applying a standard design principle (subdividing layers) to achieve predictable results (improved thermoforming and bonding).

4. Arguments Regarding Discretionary Denial

• Petitioner argued that discretionary denial under 35 U.S.C. §314(a) would be inappropriate. It stipulated that, if the IPR is instituted, it will not pursue in a parallel district court case any invalidity ground that was raised or could have been reasonably raised in the petition, thereby mitigating concerns over duplicative efforts and potentially conflicting decisions.

5. Relief Requested

• Petitioner requests institution of an inter partes review and cancellation of claims 1-11 of Patent 11,648,090 as unpatentable.