PTAB

IPR2022-00061

Promethean Ltd v. FlatFrog Laboratories Ab

Key Events

Petition

petition

Title: Touch Sensing Apparatus and Method for Assembly
Brief Description: The ’916 patent relates to touch panels that use infrared light transmitted above a touch surface to detect the location of objects. The invention focuses on a specific support structure and sealing mechanism for the optical components.

Prior Art Relied Upon: Chen ’221 (PCT Publication No. WO 2014/131221).
Core Argument for this Ground:
- Prior Art Mapping: Petitioner argued that Chen ’221, which discloses a "projection-type touch control electronic whiteboard," teaches every limitation of the challenged claims. Specifically, Chen ’221’s frame (100) is a support structure with a first portion that includes two discrete, downward-jutting projections forming a trapezoidal receptacle. This receptacle receives a mating portion of an optical element, filter (300), which is fitted in the space between the panel and the frame to seal the emitters from contaminants. Petitioner asserted that Chen ’221 also discloses the features of dependent claims 2, 3, and 5, including a second portion of the support structure for mounting an electronics board that emits light above the touch surface and an optical element with specific angled surfaces.

Prior Art Relied Upon: Hu (Chinese Application Publication No. CN 104391611A) and Chen ’221 (PCT Publication No. WO 2014/131221).
Core Argument for this Ground:
- Prior Art Mapping: Petitioner contended that Hu, an infrared touch device, discloses all limitations of claim 1 except for a second projection extending downwards from the support structure’s first portion. Hu’s device has a gap formed between a first downward projection (P1) and a second part (P2) that is level with, but does not extend downward from, the first portion.
- Motivation to Combine: A Person of Ordinary Skill in the Art (POSITA) would have been motivated to modify Hu by incorporating the two-projection receptacle taught by Chen ’221. Chen ’221 taught that securing an IR filter between two downward projections was a known, effective design. A POSITA would combine these teachings to improve the mounting and sealing of Hu's IR filter, which was a simple substitution of one known element for another to achieve a predictable result.
- Expectation of Success: The modification was argued to be a routine and obvious design choice, as the claimed two-projection configuration was well known in the art for securing optical components, leading to a high expectation of success.

Prior Art Relied Upon: Mo (Chinese Utility Model Patent CN 204288179), Chen ’221, and/or Hu.
Core Argument for this Ground:
- Prior Art Mapping: Petitioner argued that Mo’s infrared whiteboard frame structure meets nearly all limitations of claim 1. However, Mo does not explicitly state that its emitters and detectors are arranged along the entire perimeter of the whiteboard body, nor that its optical element (light filter bar 2) extends along the entire perimeter to fully "seal" the emitters.
- Motivation to Combine: A POSITA would have found it obvious to modify Mo based on the teachings of Chen ’221 and Hu. Both references disclose that arranging emitters, detectors, and a sealing optical element around the entire perimeter is a conventional and necessary configuration for creating a functional light matrix for touch detection. A POSITA would apply this known technique to Mo to improve its touch-sensing functionality and protect its optical components, a predictable improvement.
Additional Grounds: Petitioner asserted additional obviousness challenges, including that claims 1-3 are obvious over Chen ’812 in view of Chen ’221, and that claims 4 and 9 (relating to a slidable optical element) are obvious over the primary combinations further in view of Chen ’707, which taught a slidable filter for easier maintenance.

"said first portion including a first projection... and a second projection...": Petitioner proposed this be construed as requiring two structures that "jut out downward from and are discrete from the first portion." This construction emphasizes that the projections are distinct features extending from the main structure, not recesses within it, which is central to their argument that Hu does not fully anticipate.
"fitted in the space... and configured to seal...": Petitioner argued this requires the optical element to be "disposed within all or part of the separation between the first portion and the panel" to prevent the ingress of some, but not necessarily all, contaminants. This construction avoids a requirement that the element fill the entire space or create a perfect seal.
"supported by" (claim 3): Following a district court ruling, Petitioner construed this term as "directly or indirectly held in position by," allowing for intermediate components between the electronics board and the second portion of the support structure.

§325(d) - Cumulative Art: Petitioner argued denial is improper because the primary prior art references (Chen ’221, Hu, Mo, Chen ’812) were never considered by the examiner during prosecution. The examiner instead focused on a different reference (Eriksson) that lacked the key claimed feature of two downward projections, meaning the asserted grounds are not cumulative.
§314(a) - Fintiv Factors: Petitioner argued the Fintiv factors weigh in favor of institution. They asserted that the trial date in the parallel district court litigation is speculative and subject to change, that they acted diligently in filing the petition after the ’916 patent was asserted, and that they have stipulated not to pursue the same invalidity grounds in district court if the IPR is instituted, thereby mitigating concerns of duplicative efforts.

Petitioner requests institution of inter partes review and cancellation of claims 1-5 and 9 of the ’916 patent as unpatentable.