CaptionCall LLC v. Ultratec Inc

1. Case Identification

• Case #: IPR2015-01359
• Patent #: 6,493,426
• Filed: June 8, 2015
• Petitioner(s): CaptionCall, L.L.C.
• Patent Owner(s): Ultratec, Inc.
• Challenged Claims: 1-3 and 5-7

2. Patent Overview

• Title: Relay for Personal Interpreter
• Brief Description: The ’426 patent describes a telecommunications relay system designed to assist users with hearing impairments. The system uses a human call assistant to re-voice a hearing user's speech into a voice recognition system, which generates a text transcription that is then transmitted, along with the original voice audio, to the assisted user's device.

3. Grounds for Unpatentability

Ground 1: Obviousness over Engelke ’482, Engelke ’405, and Hiroi - Claims 1-3 and 5-7 are obvious over Engelke ’482, Engelke ’405, and Hiroi.

• Prior Art Relied Upon: Engelke ’482 (Patent 5,909,482), Engelke ’405 (Patent 5,724,405), and Hiroi (Japanese Patent Publication 10-234016).
• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that the combination of the three references taught every limitation of the challenged claims. Engelke ’482, a parent patent to the ’426 patent, disclosed the foundational "revoicing relay" system where a call assistant listens to a hearing user and speaks their words into a trained speech recognition system to generate a text stream for a deaf user. This reference taught the core method steps of transmitting a hearing user's voice to a call assistant, the assistant re-voicing the words into a digital computer, and the computer translating the speech to a digital text stream for transmission to the user.

    However, Engelke ’482 was designed for deaf users and only transmitted text. Petitioner asserted that Engelke ’405, by the same inventor, addressed the needs of hard-of-hearing users by teaching a "text enhanced telephone" system that transmitted both the hearing user's voice and the corresponding text transcription over a common telephone line. This provided the missing element of transmitting both voice and text to the assisted user.

    Finally, Petitioner argued that Hiroi addressed the problem of synchronizing audio and text. Hiroi disclosed a system that uses a buffer to delay an audio signal so that its corresponding text transcription (captions) can be generated and transmitted synchronously, creating a more natural user experience. This taught the claimed limitation of delaying the hearing user's voice to make the received text and voice closer to synchrony. Dependent claims 2 and 3, which recite a "fixed" and "variable" delay, respectively, were also argued to be taught by Hiroi.

  • Motivation to Combine: Petitioner contended that a person of ordinary skill in the art (POSITA) would have been motivated to combine the references for predictable results. First, a POSITA would combine the text-only relay of Engelke ’482 with the teachings of Engelke ’405 to improve the system for hard-of-hearing users, not just deaf users. This was presented as applying a known technique (adding voice transmission) from one of the inventor's own patents to improve a similar device.

    Second, after combining Engelke ’482 and ’405 to create a system transmitting both voice and text, a POSITA would have recognized the known problem of asynchrony between the two streams. Hiroi explicitly taught a solution: delaying the audio with a buffer. A POSITA would have been motivated to incorporate Hiroi’s buffering system into the combined Engelke relay to improve its usability, which was a predictable solution to a known problem.

  • Expectation of Success: Petitioner argued a POSITA would have had a reasonable expectation of success. The technologies were compatible; Engelke ’405 already taught how to combine voice and text streams on a telephone line. Furthermore, Engelke ’482 disclosed a computer-based relay system, and implementing Hiroi's audio buffer in software on that existing computer would have been a straightforward task for a POSITA. Engelke ’482 even disclosed a simple "voice input buffer" to prevent the call assistant from falling behind, showing that buffering was already contemplated in the base system.

4. Key Claim Construction Positions

• "assisted user": Petitioner proposed construing this term to mean "a user who may be deaf or hard of hearing, but who also may be a normally hearing person who simply wants text assistance for some reason." This construction, based on the patent’s specification, was important for establishing the relevance of prior art like Engelke ’405, which was directed at users who were hard-of-hearing rather than completely deaf.

5. Key Technical Contentions (Beyond Claim Construction)

• Priority Date of the ’426 Patent: A central contention of the petition was that the challenged claims of the ’426 patent were not entitled to the priority date of the parent Engelke ’482 application. Petitioner argued that the ’426 patent added new matter not disclosed in Engelke ’482, specifically the concepts of (1) transmitting the hearing user’s original voice to the assisted user and (2) delaying that voice transmission for synchronization with the text. Because this new matter was essential to the challenged claims, their effective priority date was the filing date of the ’426 patent application (February 14, 2001). This argument was critical, as it established that Engelke ’482, published in 1999, qualified as prior art against the ’426 patent under 35 U.S.C. §102(b).

6. Relief Requested

• Petitioner requested institution of an inter partes review and cancellation of claims 1-3 and 5-7 of the ’426 patent as unpatentable.