DCT

1:26-cv-00918

Electronics Telecommunications Research Institute v. Snap Inc

Log In
Key Events
Amended Complaint
complaint Intelligence

I. Executive Summary and Procedural Information

  • Parties & Counsel:
  • Case Identification: 1:26-cv-00918, D. Del., 09/25/2026
  • Venue Allegations: Venue is alleged to be proper as Defendant is incorporated in Delaware and has allegedly committed acts of patent infringement in the district.
  • Core Dispute: Plaintiffs allege that Defendant’s Snapchat application and associated backend services infringe six U.S. patents related to video coding technology compliant with the H.265/HEVC standard.
  • Technical Context: The technology at issue is digital video compression, specifically techniques for improving the efficiency of the High Efficiency Video Coding (HEVC) standard, which is critical for delivering high-quality video content over internet networks.
  • Key Procedural History: The complaint details pre-suit licensing negotiations between Defendant and Access Advance, a patent pool that includes the Asserted Patents. Plaintiffs allege these negotiations, which included providing patent charts and royalty explanations, establish Defendant's knowledge of the patents and form the basis for a willfulness claim. The complaint also references the patents’ development history through contributions to the JCT-VC standards body and includes a declaratory judgment count that Plaintiffs have complied with their reasonable and non-discriminatory (RAND) licensing obligations.

Case Timeline

Date Event
2008-10-01 ’996 Patent Priority Date
2008-10-06 VCEG submission related to ’996 Patent
2011-06-20 ’416 and ’820 Patents Priority Date
2011-07-01 JCT-VC submission related to ’416 and ’820 Patents
2011-09-16 ’168 Patent Priority Date
2012-01-20 JCT-VC submission related to ’182 Patent
2012-04-16 ’643 Patent Priority Date
2018-01-30 U.S. Patent No. 9,883,182 Issues
2018-06-19 U.S. Patent No. 10,003,820 Issues
2018-07-10 U.S. Patent No. 10,021,416 Issues
2019-01-29 U.S. Patent No. 10,194,168 Issues
2020-08-11 U.S. Patent No. 10,742,996 Issues
2023-02-28 U.S. Patent No. 11,595,643 Issues
2023-11-24 Plaintiffs allege Snap had knowledge of Asserted Patents
2024-05-30 Re-Examination Decision on a related patent
2025-08-13 Access Advance allegedly contacts Snap to offer license
2025-11-21 Access Advance allegedly sends Snap a patent chart
2025-11-24 Phone call between Access Advance and Snap
2026-01-15 Access Advance allegedly sends Snap licensing documents
2026-03-03 Snap allegedly sends draft NDA to Access Advance
2026-03-25 Access Advance allegedly informs Snap of litigation in Brazil
2026-09-25 Complaint Filing Date

II. Technology and Patent(s)-in-Suit Analysis

U.S. Patent No. 11,595,643 - "Encoding method and decoding method, and device using same"

  • Patent Identification: U.S. Patent No. 11,595,643, "Encoding method and decoding method, and device using same," issued February 28, 2023 Compl. ¶53

The Invention Explained

  • Problem Addressed: In digital video coding, data for brightness (luma) and color (chroma) are often handled separately Compl. ¶56 Prior art techniques for processing pixel data, such as zigzag scanning, did not adapt the subsequent frequency transform (e.g., Discrete Cosine Transform (DCT) or Discrete Sine Transform (DST)) to the specific circumstances of the coding, resulting in inefficiency Compl. ¶59
  • The Patented Solution: The invention proposes to improve encoding efficiency by adaptively selecting the type of frequency transform based on criteria like the intra-prediction mode and block size Compl. ¶60 ’643 Patent, 10:51-55 For example, for a 4×4 luma block, the patent teaches applying DST in both horizontal and vertical directions for all intra-prediction modes to improve the encoding efficiency of the residual signals Compl. ¶61
  • Technical Importance: This adaptive transform selection provides substantial benefits to encoding and decoding efficiency, leading to smaller video bitstreams, particularly for high-resolution video Compl. ¶55

Key Claims at a Glance

  • The complaint asserts at least exemplary Claim 2 Compl. ¶124
  • The essential elements of independent Claim 2, a method claim, are:
    • deriving an intra prediction mode of a current block;
    • determining a scan type of the current block based on the intra prediction mode;
    • deriving residual coefficients of the current block based on the scan type;
    • determining a transform type of the current block to be a DCT or a DST; and
    • performing an inverse-transform on the residual coefficients based on the transform type, wherein for a 4×4 luma component block, the inverse-transform is performed using DST in horizontal and vertical transform directions for all intra prediction direction modes and a planar mode.
  • The complaint does not explicitly reserve the right to assert dependent claims for this patent.

U.S. Patent No. 9,883,182 - "Method and apparatus for setting reference picture index of temporal merging candidate"

  • Patent Identification: U.S. Patent No. 9,883,182, "Method and apparatus for setting reference picture index of temporal merging candidate," issued January 30, 2018 Compl. ¶66

The Invention Explained

  • Problem Addressed: In video compression, "merge mode" reuses motion information from neighboring blocks to improve efficiency Compl. ¶68 A key piece of this information is the "reference picture index." Prior art methods required this index to be derived serially from neighboring blocks that had already been processed, which created a bottleneck and prevented parallel processing of multiple prediction blocks within a single coding block Compl. ¶¶69, 72
  • The Patented Solution: The invention breaks this serial dependency by providing methods to derive the reference picture index without waiting for other blocks to be processed Compl. ¶70 This is achieved by either replacing an unavailable spatial merging candidate with an already-coded block from outside the current coding block, or by setting the reference picture index to a fixed value, such as zero '182 Patent, 17:50-18:25 Compl. ¶70 This allows inter-frame prediction to be performed on prediction blocks in parallel Compl. ¶71
  • Technical Importance: Enabling parallel processing of prediction blocks significantly increases processing speed and coding efficiency, which is particularly beneficial for high-throughput applications like high-definition video Compl. ¶71

Key Claims at a Glance

  • The complaint asserts at least exemplary Claim 1 Compl. ¶134
  • The essential elements of independent Claim 1, a method claim, include:
    • selecting a collocated picture and deriving spatial and temporal merging candidates;
    • generating a merging candidate list comprising the spatial and temporal merging candidates;
    • determining a motion vector and reference picture index using the list;
    • obtaining prediction samples and residual samples to generate a reconstructed block;
    • wherein while a reference picture index of the spatial merging candidate is determined from its neighboring block, a reference picture index of the temporal merging candidate is set to a fixed value of zero; and
    • wherein the neighboring blocks are determined based on the position and size of the coding block.
  • The complaint does not explicitly reserve the right to assert dependent claims for this patent.

U.S. Patent No. 10,021,416 - "Method, apparatus, and bitstream for generating reconstructed blocks using filter for intra prediction mode"

  • Patent Identification: U.S. Patent No. 10,021,416, "Method, apparatus, and bitstream for generating reconstructed blocks using filter for intra prediction mode," issued July 10, 2018 Compl. ¶77
  • Technology Synopsis: The patent addresses prediction errors and inter-block discontinuities that arise during intra-prediction in video coding Compl. ¶79 It proposes an unconventional method of filtering prediction pixels where the filter type, target region, and filter characteristics are determined based on the intra-prediction mode and are fixed for a plurality of block sizes, improving prediction efficiency Compl. ¶¶80-81 The filtering is selectively applied to blocks smaller than 32×32 where it is most effective Compl. ¶80
  • Asserted Claims: Exemplary Claim 1 Compl. ¶144
  • Accused Features: Snap's encoding of bitstreams into H.265-compliant (HEVC) formats on its servers Compl. ¶139

U.S. Patent No. 10,194,168 - "Method for inducing prediction motion vector and apparatuses using same"

  • Patent Identification: U.S. Patent No. 10,194,168, "Method for inducing prediction motion vector and apparatuses using same," issued January 29, 2019 Compl. ¶86
  • Technology Synopsis: The patent seeks to reduce computational complexity in inter-frame prediction by conditionally determining whether to derive a temporal candidate prediction motion vector Compl. ¶¶87, 89 The invention determines the temporal candidate is "unavailable" (i.e., skips its derivation) when two distinct spatial candidate prediction motion vectors are already available, thereby avoiding an unnecessary processing step Compl. ¶90
  • Asserted Claims: Exemplary Claim 4 Compl. ¶154
  • Accused Features: Snap's encoding and/or decoding of bitstreams in H.265-compliant (HEVC) formats on its servers Compl. ¶149

U.S. Patent No. 10,742,996 - "Image encoder and decoder using unidirectional prediction"

  • Patent Identification: U.S. Patent No. 10,742,996, "Image encoder and decoder using unidirectional prediction," issued August 11, 2020 Compl. ¶96
  • Technology Synopsis: The patent addresses degraded prediction accuracy in conventional intra-prediction where the encoding order of sub-blocks was fixed Compl. ¶¶99-100 The invention determines the encoding and decoding order of sub-blocks based on the intra-prediction mode, ensuring that each sub-block is processed with reference to an already-decoded adjacent block, which reduces prediction errors Compl. ¶¶101-102
  • Asserted Claims: Exemplary Claim 1 Compl. ¶164
  • Accused Features: Snap's encoding and/or decoding of bitstreams in H.265-compliant (HEVC) formats on its servers Compl. ¶159

U.S. Patent No. 10,003,820 - "Image encoding/decoding method and apparatus for same"

  • Patent Identification: U.S. Patent No. 10,003,820, "Image encoding/decoding method and apparatus for same," issued June 19, 2018 Compl. ¶107
  • Technology Synopsis: Similar to the ’416 Patent, this invention aims to reduce prediction error and block discontinuities by applying a filter determined by the intra-prediction mode Compl. ¶¶109-110 The patent specifically teaches a 3-tap filter for the DC mode with fixed coefficients (2/4 for the DC value, 1/4 for the upper reference pixel, 1/4 for the left reference pixel) to create smoother predictions and simplify the encoding process Compl. ¶111
  • Asserted Claims: Exemplary Claim 3 Compl. ¶174
  • Accused Features: Snap's encoding and/or decoding of bitstreams in H.265-compliant (HEVC) formats on its servers Compl. ¶169

III. The Accused Instrumentality

Product Identification

  • The "Accused Services" are identified as Snap Inc.'s applications and backend processes, including the core "Snapchat" product, that use video coding technology Compl. ¶5

Functionality and Market Context

  • The complaint alleges that a core function of Snapchat is transmitting high-quality video Compl. ¶26 When a user posts a "Story," Snap's backend servers transcode the video into multiple digitally compressed variants at different resolutions and bitrates Compl. ¶27 The complaint cites a Snap engineering blog post stating that Snap uses the H.265 (HEVC) standard to "deliver the same video quality with a smaller bitrate" Compl. ¶28 The complaint provides charts from this blog post showing that GPU-transcoded HEVC videos achieve bitrate reduction with slightly better quality than H.264 videos Compl. ¶29 A side-by-side visual from the same source illustrates that an HEVC video at 563 kb/s has better quality than an H.264 video at 676 kb/s Compl. ¶30

IV. Analysis of Infringement Allegations

The complaint references but does not include the exemplary claim charts as exhibits Compl. ¶125 Compl. ¶135 The infringement theory is summarized below in prose.

  • ’643 Patent Infringement Allegations
    The complaint alleges that Snap’s Accused Services directly infringe at least Claim 2 of the ’643 Patent through their encoding of bitstreams into H.265-compliant (HEVC) formats on servers in the United States Compl. ¶119 Compl. ¶125 The narrative theory is that by implementing the HEVC standard, Snap’s servers necessarily perform the claimed method steps, which include deriving an intra prediction mode, determining a scan type, deriving residual coefficients, determining a transform type (DCT or DST), and performing an inverse-transform using DST for 4×4 luma component blocks under specified conditions Compl. ¶124

  • ’182 Patent Infringement Allegations
    The complaint alleges that Snap’s Accused Services directly infringe at least Claim 1 of the ’182 Patent through their decoding of H.265-compliant (HEVC) bitstreams on servers Compl. ¶129 Compl. ¶135 The infringement theory centers on Snap’s use of the HEVC standard's "merge mode." It is alleged that this implementation performs the claimed steps of deriving spatial and temporal merging candidates to generate a merging list, and crucially, sets the reference picture index of the temporal merging candidate to "a fixed value of zero" when the corresponding spatial candidate's index is determined from a neighboring block, a key step for enabling parallel processing as claimed Compl. ¶134

V. Key Claim Terms for Construction

  • For the ’643 Patent:

    • The Term: "inverse-transform" (from Claim 2)
    • Context and Importance: The claim requires "performing an inverse-transform," and the final limitation specifies that this is performed using DST under certain conditions for a luma component Compl. ¶124 The infringement analysis will depend on whether Snap's HEVC implementation performs a process that meets the definition of this term and satisfies the specific DST usage condition.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The specification discusses various transforms, including "integer transform, integer DCT, integer DST," as examples of frequency domain transforms Compl. ¶60 ’643 Patent, 10:51-55 A party may argue that "inverse-transform" should be construed broadly as the reversal of any such frequency domain transform used in the art.
      • Evidence for a Narrower Interpretation: The claim itself provides a very specific context, tying the "inverse-transform" to the use of "DST in horizontal and vertical transform directions, for all intra prediction direction mode and a planar mode" for a 4x4 luma block Compl. ¶124 A party may argue this detailed description acts as a definitional constraint on the term's scope.

  • For the ’182 Patent:

    • The Term: "a fixed value of zero" (from Claim 1)
    • Context and Importance: This term is a central element of the claimed solution for enabling parallel processing. Practitioners may focus on this term because the infringement question may turn on whether Snap's accused decoders set the reference picture index to literally "zero" as claimed, or use a different fixed value or an entirely different mechanism.
    • Intrinsic Evidence for Interpretation:
      • Evidence for a Broader Interpretation: The patent's stated goal is to enable parallel processing by breaking a serial dependency Compl. ¶71 A party might argue that the invention is the use of any predetermined, non-dependent value to break the chain, and that "zero" is merely an exemplary embodiment of such a "fixed value" '182 Patent, 17:50-18:25
      • Evidence for a Narrower Interpretation: The claim language is precise: "a fixed value of zero" Compl. ¶134 A party may argue that the plain language requires the value to be exactly zero. The complaint also highlights the Examiner’s recognition during prosecution of setting the index "to a specific value," which may suggest that the fixed nature, rather than the specific value of zero, is the core of the invention, but a defendant could still argue the claim itself is limited to zero Compl. ¶75

VI. Other Allegations

  • Indirect Infringement: Plaintiffs allege that Snap induces infringement of all asserted patents by directing its "partners and vendors" and "service providers" to perform acts that directly infringe the patent claims Compl. ¶120 Compl. ¶130 Compl. ¶140 Compl. ¶150 Compl. ¶160 Compl. ¶170 The complaint alleges Snap performs these acts with knowledge and intent.
  • Willful Infringement: Willfulness is alleged for all asserted patents Compl. ¶122 Compl. ¶132 Compl. ¶142 Compl. ¶152 Compl. ¶162 Compl. ¶172 The allegations are based on alleged pre-suit knowledge, stemming from Snap's status as an HEVC Advance pool licensee since at least November 24, 2023, and direct communications from the Access Advance patent pool beginning in 2025 Compl. ¶¶52, 118

VII. Analyst’s Conclusion: Key Questions for the Case

  • A core issue will be one of standard-essential infringement: does implementing the H.265/HEVC video coding standard, as Defendant allegedly does, necessarily result in infringement of the specific methods recited in the asserted patent claims? The case will likely require a granular comparison of the standard's technical requirements against the claim limitations.
  • A key evidentiary question will be one of technical implementation: for the '182 Patent, does the accused decoding process set a reference picture index to "a fixed value of zero" as literally claimed, or does it employ a different mechanism to achieve parallel processing? For the '643 Patent, does the accused encoding process perform an "inverse-transform" using DST under the exact conditions specified in Claim 2, or is there a functional or operational mismatch?
  • A central legal and factual question will be the parties' compliance with RAND obligations. Given the patents are presented as essential to a widely adopted standard, the case may heavily feature arguments regarding whether Plaintiffs' licensing offers, made through the Access Advance patent pool, were on reasonable and non-discriminatory terms, an issue Plaintiffs have proactively raised in a count for declaratory judgment.