Elo Touch Solutions, Inc. v. 3M Innovative Properties Company

1. Case Identification

• Case #: Not Yet Assigned
• Patent #: 9,823,786
• Filed: November 11, 2018
• Petitioner(s): Elo Touch Solutions, Inc. and MNtech Co. Ltd.
• Patent Owner(s): 3M Innovative Properties Company
• Challenged Claims: 1-14

2. Patent Overview

• Title: TOUCH SCREEN SENSOR
• Brief Description: The ’786 patent describes touch screen sensors that use an electrically conductive micropattern instead of a traditional continuous coating of transparent conducting oxide (TCO). The invention purports to improve control over electrical properties without compromising optical quality by using a structure where a visible light transparent conductive mesh region and a larger, non-transparent feature are formed from the same metal at approximately the same thickness.

3. Grounds for Unpatentability

Ground 1: Obviousness over Okumura - Claims 1-6, 12, and 14 are obvious over Okumura.

• Prior Art Relied Upon: Okumura (Japanese Application # JP 2006-344163).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Okumura teaches all elements of independent claim 1. Okumura discloses an electrostatic capacitance touch panel with a transparent substrate, and a micropattern comprising a "network structure" of ultra-fine metallic conductors. This network forms a visible light transparent mesh region with enclosed open areas. Okumura also discloses non-transparent portions, such as electrode terminals ("non-openings 2"), which constitute a larger feature. Petitioner contended that while Okumura does not explicitly state the mesh and the larger feature are the same metal at the same thickness, a person of ordinary skill in the art (POSITA) would find it obvious to form both features from a single metallic film via a single etching process for manufacturing simplicity, which would inherently result in the same metal and thickness. Dependent claims are allegedly met by Okumura's disclosure of conductive traces (claim 2), pads (claim 5), specific open area percentages (claim 12), and irregular polygon shapes (claim 14).
  • Motivation to Combine (for §103 grounds): The motivation to render the final element obvious was based on a POSITA's knowledge. A POSITA would have recognized the desirability of forming Okumura's electrode and integrated terminal in a single process to reduce manufacturing complexity and cost.
  • Expectation of Success: A POSITA would have a high expectation of success, as forming a patterned mesh and a solid feature by etching a single layer of metallic film was a common and well-understood manufacturing technique.

Ground 2: Obviousness over Okumura and Chen - Claims 7-11 are obvious over Okumura in view of Chen.

• Prior Art Relied Upon: Okumura (Japanese Application # JP 2006-344163) and Chen (Application # 2007/0018076).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground built upon the Okumura-based challenge for claim 1 and addressed the additional limitations of dependent claims 7-11, which recite specific narrow trace widths (ranging from ≤0.5 µm to ≤10 µm). Petitioner argued that Okumura teaches the foundational touch screen structure, while Chen teaches using narrow trace widths within the claimed ranges for electromagnetic digitizer sensor arrays. Chen explicitly discloses trace widths from 500 nm (0.5 µm) to 500 µm, encompassing all the ranges claimed in claims 7-11, as a matter of design choice to enhance sensitivity and resolution.
  • Motivation to Combine (for §103 grounds): A POSITA would combine Chen’s teachings on trace widths with Okumura's sensor design to improve the sensitivity and resolution of Okumura's device. This was a conventional goal, and Chen taught that using such trace widths was a known method for achieving it.
  • Expectation of Success: Success would be expected because fabricating finer trace widths using conventional photolithographic processes, as disclosed by both references, was a well-known and predictable design modification.

Ground 3: Obviousness over Yang - Claims 1-6 and 12 are obvious over Yang.

• Prior Art Relied Upon: Yang (Patent 8,619,039).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner asserted that Yang, which discloses a semi-transparent touch screen device, teaches every element of the independent claim. Yang's device includes a mesh of low-resistive material (e.g., copper) on a transparent film substrate. This mesh constitutes the transparent conductive mesh region with open areas. Petitioner argued that Yang's figures show this mesh is integral and continuous with a larger, non-transparent feature used for electrical connection (circuitry 224). Because Yang’s mesh is formed through a single "printing, masking and a blackening process," the mesh and the larger feature are inherently made of the same material at the same thickness. Dependent claims are allegedly met by Yang's disclosure of the larger feature being a conductive trace (claim 2), its connection to a PCB pad (claim 5), and its calculated open area fraction of 93.4% (claim 12).
  • Motivation to Combine (for §103 grounds): Not applicable, as this is a single-reference ground.
  • Expectation of Success: Not explicitly argued, but implied as Yang's disclosure is presented as a direct mapping.

• Additional Grounds: Petitioner asserted additional obviousness challenges, including combining Okumura with Yoshikawa for claim 13 (open area fraction), combining Yang with Chen for claims 7-11 (trace widths), combining Yang with Yoshikawa for claim 13 (open area fraction), and combining Yang with Okumura for claim 14 (irregular polygon shapes). These grounds relied on similar rationales of combining primary sensor structures with secondary art teaching routine optimization of known design variables.

4. Key Technical Contentions (Beyond Claim Construction)

• Obvious Manufacturing Process: A central technical contention was that the allegedly novel feature of the ’786 patent—having the transparent mesh and the larger non-transparent feature made of the same metal at the same thickness—is not an inventive step. Rather, it is an obvious and inherent result of using a standard, cost-effective manufacturing process like etching or printing a pattern from a single, continuous layer of metal.
• Result-Effective Variables: Petitioner contended that parameters such as trace width and open area fraction were well-known "result-effective variables" in the art. A POSITA would have routinely optimized these parameters to balance competing design goals like transparency, conductivity, and sensor resolution, making their selection a matter of ordinary skill, not invention.

5. Arguments Regarding Discretionary Denial

• Related Litigation: Petitioner noted that the ’786 patent is the subject of co-pending patent infringement lawsuits brought by the patent owner against Petitioner Elo Touch Solutions, Inc. in the U.S. District Court for the District of Delaware. This statement of fact establishes the potential for discretionary denial under §314(a) based on the Fintiv factors, although the petition did not present explicit arguments against such a denial.

6. Relief Requested

• Petitioner requested that the Board institute an inter partes review and cancel claims 1-14 of the ’786 patent as unpatentable.