Google LLC v. Ericsson Ab

1. Case Identification

• Case #: IPR2025-00003
• Patent #: 9,313,178
• Filed: October 1, 2024
• Petitioner(s): Google LLC and Lenovo (United States) Inc.
• Patent Owner(s): Ericsson Ab
• Challenged Claims: 1-8, 10, 12, 14, 16-20

2. Patent Overview

• Title: Encryption Key Rotation for Live Streaming Media
• Brief Description: The ’178 patent discloses a method for securely distributing streaming multimedia content, such as over-the-top (OTT) delivery. The system uses segmented content where segments are protected by a rotation of serial, time-limited encryption keys, and a client device pre-fetches a new key from a license server before the current key expires to prevent playback interruptions.

3. Grounds for Unpatentability

Ground 1: Obviousness over Peterka - Claims 1-6, 10, 12, 16-18, and 20 are obvious over Peterka.

• Prior Art Relied Upon: Peterka (Application # 2002/0172368).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Peterka discloses all elements of the independent claims. Peterka teaches a secure multimedia distribution system with a "pull model" where clients monitor the expiration times of encryption keys and request new keys "before the current keys expire so as to avoid service interruptions." This client-side monitoring and proactive requesting directly maps to the ’178 patent’s concept of detecting a key rotation boundary and issuing requests to a license server ahead of that boundary. Petitioner asserted that Peterka’s disclosure of streaming media at various bit rates would have made the use of conventional manifest files to manage such adjustments obvious to a person of ordinary skill in the art (POSITA).
  • Motivation to Combine: Not applicable for a single-reference ground. However, Petitioner argued a POSITA would have been motivated to implement Peterka’s adaptive bit-rate streaming capabilities using well-known manifest files to provide necessary encoding information to the client.
  • Expectation of Success: A POSITA would have a high expectation of success in using manifest files with Peterka’s system, as this was a conventional and predictable method for implementing adaptive bit-rate streaming.

Ground 2: Obviousness over Peterka in view of Suzuki - Claims 1-6, 10, 12, 16-18, and 20 are obvious over Peterka in view of Suzuki.

• Prior Art Relied Upon: Peterka (Application # 2002/0172368) and Suzuki (Japanese Application # 2004-166153).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner contended that to the extent Peterka does not explicitly teach certain limitations, Suzuki supplies them. Suzuki addresses eliminating "confirmation delay" in key changes by teaching a client that uses "key numbers" (content encryption key identifiers) and "remaining validity time" (content encryption key expiration times) to determine when to request a new key. Suzuki’s client requests the next key when the current key’s validity time reaches a specific "setting value," thereby teaching the timing of prefetching a next key a fixed duration before expiration.
  • Motivation to Combine: A POSITA would combine Suzuki's detailed implementation with Peterka's broader streaming framework to enhance reliability. Suzuki provides a specific, known solution for managing key tracking and timing pre-fetching, which Peterka describes more generally. This combination would predictably improve Peterka's system by ensuring timely key acquisition and avoiding service interruptions, a stated goal of both references.
  • Expectation of Success: There would be a reasonable expectation of success, as Suzuki's teachings provide a concrete method for implementing the general functionality described in Peterka, and both references operate in the same field of secure, segmented media delivery.

Ground 3: Obviousness over Peterka in view of Bocharov - Claims 1-6, 10, 12, 14, 16-18, and 20 are obvious over Peterka in view of Bocharov.

• Prior Art Relied Upon: Peterka (Application # 2002/0172368) and Bocharov (Application # 2010/0235528).

• Core Argument for this Ground:

  • Prior Art Mapping: Petitioner argued that Bocharov remedies any alleged deficiency in Peterka regarding the retrieval of manifest files. Bocharov explicitly teaches streaming media fragments with associated "manifest" files that contain metadata, including information on available bit rates for adaptive streaming. For claims 12 and 14, Petitioner asserted that Bocharov’s manifest files provide notifications for switching encodings, which would necessitate a new decryption key and thus constitute the detection of an "actual key rotation boundary." Bocharov also teaches the use of specific manifest file types, such as IIS Smooth Streaming manifests.
  • Motivation to Combine: A POSITA would combine Bocharov's manifest file teachings with Peterka's system to implement the adaptive bit-rate streaming functionality that Peterka discloses is desirable. Bocharov provides an effective and known method for a client to receive information needed to switch between different quality streams, directly complementing Peterka's system.
  • Expectation of Success: A POSITA would reasonably expect success, as both references relate to streaming segmented media, and using manifest files to manage adaptive bit-rate streaming was a conventional technique.

• Additional Grounds: Petitioner asserted an additional obviousness challenge based on the combination of Peterka, Suzuki, and Bocharov (Ground 4). Petitioner also challenged claims 7-8 and 19 as obvious over the combination of Peterka, Bocharov, Peterka308, and Chen (Ground 5), arguing these references teach predictable key identifier progressions based on timestamps or fixed content intervals.

4. Arguments Regarding Discretionary Denial

• Petitioner argued against discretionary denial under 35 U.S.C. §325 because the asserted prior art was not considered during the original prosecution.
• Petitioner further contended that denial under §314(a) based on Fintiv factors is unwarranted. The parallel district court litigation is stayed, and Petitioner noted that the PTAB no longer applies Fintiv to parallel ITC proceedings. Furthermore, Petitioner argued that there is no parallel litigation between Google and the Patent Owner.
• Petitioner also asserted that a prior inter partes review (IPR2022-00618) involving similar grounds, which was terminated due to settlement, creates a strong reason to grant institution to obtain a final determination on patentability, especially since the current Petitioners were not party to that prior IPR.

5. Relief Requested

• Petitioner requests institution of inter partes review and cancellation of claims 1-8, 10, 12, 14, and 16-20 of the ’178 patent as unpatentable.