DCT
6:19-cv-00428
Stcunm v. Apple
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Stcunm (New Mexico)
- Defendant: Apple Inc. (California)
- Plaintiff’s Counsel: Parker, Bunt & Ainsworth, P.C.; Shore Chan DePumpo LLP
- Case Identification: 6:19-cv-00428, W.D. Tex., 07/19/2019
- Venue Allegations: Plaintiff alleges venue is proper because Defendant maintains regular and established places of business in the district, including its second-largest corporate office and numerous retail stores.
- Core Dispute: Plaintiff alleges that Defendant’s wireless communication products, including iPhones, iPads, and MacBooks, infringe three patents related to improving the efficiency and performance of wireless data transmission.
- Technical Context: The technologies at issue concern methods for providing channel feedback, structuring data frames, and allocating data bits in advanced wireless systems like MIMO and OFDMA, which are foundational to modern Wi-Fi and cellular standards.
- Key Procedural History: The patents-in-suit were originally assigned to the Industrial Technology Research Institute (ITRI), later conveyed to Sino Matrix Technology, Inc. (SMT), and ultimately assigned to Plaintiff Stcunm. Plaintiff asserts sovereign immunity as an arm of the State of New Mexico. Subsequent to the filing of this complaint, Inter Partes Review (IPR) proceedings were initiated against the '204 and '326 patents. These proceedings resulted in the cancellation of all claims asserted in the complaint from the '204 Patent (claims 1, 11, 12) and the '326 Patent (claim 1), a development that substantially impacts the viability of the infringement contentions for those patents.
Case Timeline
| Date | Event |
|---|---|
| 2007-07-12 | U.S. Patent 8,265,096 Priority Date |
| 2008-07-08 | U.S. Patent 8,565,326 Priority Date |
| 2008-07-11 | U.S. Patent 8,249,204 Priority Date |
| 2012-08-21 | U.S. Patent 8,249,204 Issued |
| 2012-09-11 | U.S. Patent 8,265,096 Issued |
| 2013-10-22 | U.S. Patent 8,565,326 Issued |
| 2018-09-26 | Alleged Date of Actual Knowledge for all Patents-in-Suit |
| 2019-07-19 | Complaint Filing Date |
| 2020-12-28 | IPR Filed Against U.S. Patent 8,249,204 (IPR2021-00377) |
| 2021-02-23 | IPR Filed Against U.S. Patent 8,565,326 (IPR2021-00582) |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,249,204 - “Apparatus and method for channel state information feedback”
- Patent Identification: U.S. Patent No. 8,249,204, “Apparatus and method for channel state information feedback,” issued August 21, 2012.
The Invention Explained
- Problem Addressed: In multiple-input multiple-output (MIMO) wireless systems, a base station needs information about the communication channels, known as channel state information (CSI), to optimize data transmission and improve throughput (’204 Patent, col. 1:21-42). Providing this feedback from a mobile station to a base station can consume significant bandwidth if the full CSI is transmitted.
- The Patented Solution: The invention proposes a method for the mobile station to efficiently feed back CSI. The mobile station first estimates the CSI by calculating channel responses for its various communication channels. It then compresses this information, for example by selecting only the most significant "channel taps" (samples of the channel response) and then generating a smaller set of parameters to represent them. This compressed CSI is then sent to the base station, reducing the feedback overhead (’204 Patent, Abstract; col. 2:50-58).
- Technical Importance: This approach allows for more efficient use of limited wireless spectrum by reducing the amount of non-data overhead required for system optimization, a critical goal in the development of high-performance wireless standards.
Key Claims at a Glance
- The complaint asserts independent claim 1 and dependent claims 11 and 12 (Compl. ¶47).
- The essential elements of independent claim 1 are:
- A method for a mobile station to provide feedback of channel state information (CSI) to a base station.
- Estimating the CSI by calculating a plurality of channel responses for a plurality of communication channels.
- The estimating step further comprises selecting a plurality of channel taps from each of the calculated channel responses.
- Compressing the estimated CSI.
- Sending the compressed CSI as feedback to the base station.
U.S. Patent No. 8,265,096 - “Method for Constructing Frame Structures”
- Patent Identification: U.S. Patent No. 8,265,096, “Method for Constructing Frame Structures,” issued September 11, 2012.
The Invention Explained
- Problem Addressed: When evolving wireless standards, such as from IEEE 802.16e ("legacy system") to 802.16m ("new system"), there is a need for backward compatibility. A challenge is designing a single data frame structure that can simultaneously carry data for both the legacy and new systems, especially when the new system has different requirements, such as supporting higher user mobility or using different symbol periods (’096 Patent, col. 2:3-14, col. 4:56-62).
- The Patented Solution: The patent describes a method for constructing a composite data frame. The frame is built with a first section formatted for a legacy communication system and a second, different section formatted for a new communication system. The second section can be tailored for different performance characteristics, such as higher mobility, by using features like denser pilot symbols or shorter symbol periods. These sections are combined into a single frame structure, allowing legacy and new devices to coexist on the same network (’096 Patent, Abstract; col. 4:40-54).
- Technical Importance: This method provides a flexible framework for evolving wireless standards, enabling backward compatibility and the introduction of new features without requiring a complete overhaul of the network infrastructure.
Key Claims at a Glance
- The complaint asserts independent claim 8 (Compl. ¶55).
- The essential elements of independent claim 8 are:
- A method of constructing a frame structure for data transmission.
- Generating a first section with data in a first format for a first communication system.
- Generating a second section with data in a second format for a second communication system.
- The symbols of both systems co-exist in one transmission scheme.
- The second communication system has pilot symbols that are denser than those in the first communication system.
- Combining the sections to form the frame structure.
U.S. Patent No. 8,565,326 - “System and Method for Bit Allocation and Interleaving”
- Patent Identification: U.S. Patent No. 8,565,326, “System and Method for Bit Allocation and Interleaving,” issued October 22, 2013.
Technology Synopsis
The patent addresses performance in systems using Hybrid Automatic Repeat Request (HARQ), a technique for retransmitting corrupted data. The invention provides a method to improve the success of retransmissions by rearranging coded bits based on their significance (e.g., systematic vs. parity bits) and their reliability (e.g., mapping to strong or weak positions in a modulation scheme). For a retransmission, bits can be moved between reliability groups and their sequence circularly shifted to achieve greater diversity and error correction capability (’326 Patent, Abstract; col. 1:19-41).
Asserted Claims
The complaint asserts independent claim 1 (Compl. ¶63).
Accused Features
The complaint alleges the accused products employ a data transmission method where data of variable length is circularly shifted to improve communication speed, and where the shift is related to the number of space-time streams and the modulation order (Compl. ¶62).
III. The Accused Instrumentality
Product Identification
The complaint identifies a wide range of Apple’s wireless-enabled consumer electronics as the “Accused Instrumentalities.” This includes numerous models of the iPhone (from iPhone 6 to iPhone XS Max), iPad, iPad Pro, iPad Air, iPad Mini, Apple TV, iPod touch, MacBook, MacBook Air, MacBook Pro, iMac, iMac Pro, and Mac Mini (Compl. ¶44).
Functionality and Market Context
The complaint alleges that these devices are adapted to operate with wireless networks that comply with the IEEE 802.11ac standard (Compl. ¶45). The accused functionality pertains to the core wireless communication capabilities of these devices, specifically how they allegedly manage CSI feedback, structure data frames for transmission, and allocate bits for retransmissions in a manner that practices the methods claimed in the patents-in-suit (Compl. ¶¶46, 54, 62).
IV. Analysis of Infringement Allegations
No probative visual evidence provided in complaint.
’204 Patent Infringement Allegations
The complaint alleges that the Accused Instrumentalities, as mobile stations, directly infringe at least claim 1 of the ’204 Patent. The core of the infringement theory is that the devices estimate CSI, compress it, and send it as feedback to a base station, with the compression involving the selection of channel taps (Compl. ¶46).
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method for a mobile station to provide to a base station feedback of channel state information (CSI) regarding a plurality of communication channels between the mobile station and the base station... | Accused Instrumentalities are mobile stations that provide CSI feedback to a base station on a wireless network. | ¶46 | col. 4:3-10 |
| estimating the CSI by calculating a plurality of channel responses each for one of the communication channels; | The mobile station is configured to estimate CSI by calculating responses for each communication channel. | ¶46 | col. 4:30-34 |
| wherein the estimating further comprises selecting a plurality of channel taps from each of the calculated channel responses to estimate the CSI; | The mobile station is configured to select channel taps from each calculated channel response. | ¶46 | col. 4:35-42 |
| compressing the estimated CSI; | The mobile station can compress the estimated CSI. | ¶46 | col. 4:13-17 |
| and sending the compressed CSI as the feedback to the base station. | It sends the compressed CSI as feedback to the base station. | ¶46 | col. 4:6-10 |
- Identified Points of Contention:
- Scope Questions: The complaint’s allegations are articulated at a high level. A central question is whether the specific methods for CSI feedback implemented in the accused 802.11ac-compliant products fall within the scope of the claim terms, particularly "selecting a plurality of channel taps" and "compressing the estimated CSI." The defense may argue that standardized 802.11ac methods are technically distinct from the specific compression techniques disclosed in the patent, such as least-squares fitting or DCT-based parameterization (’204 Patent, col. 4:52-56, col. 7:7-13).
- Technical Questions: The complaint does not provide specific evidence detailing how the accused products perform channel tap selection or compression. The case would require discovery to determine if the accused functionality technically matches the claimed methods or operates in a fundamentally different way.
’096 Patent Infringement Allegations
The complaint alleges the Accused Instrumentalities directly infringe at least claim 8 of the ’096 Patent by employing a frame structure that combines legacy and very high throughput (VHT) formats into a unitary frame (Compl. ¶54).
| Claim Element (from Independent Claim 8) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A method of constructing a frame structure for data transmission... | Accused Instrumentalities employ a patented frame structure for data transmission. | ¶54 | col. 1:19-21 |
| generating a first section comprising data configured in a first format compatible with a first communication system... | The frame structure combines a legacy communication format... | ¶54 | col. 8:17-21 |
| generating a second section following the first section, the second section comprising data configured in a second format compatible with a second communication system... | ...and a very high throughput (VHT) communication format... | ¶54 | col. 8:21-25 |
| wherein the second communication system has pilot symbols that are denser than those in the first communication system; | The complaint alleges combination of legacy and VHT formats. It does not explicitly allege that the VHT format uses denser pilot symbols. | ¶54 | col. 5:10-15 |
| and combining the first section, the second section and the at least one non-data section to form the frame structure. | ...into a unitary frame structure. | ¶54 | col. 8:32-34 |
- Identified Points of Contention:
- Factual Questions: Claim 8 includes the specific limitation that the second communication system has "pilot symbols that are denser than those in the first communication system." The complaint alleges the use of combined "legacy" and "VHT" formats but does not explicitly plead facts to support this "denser" pilot symbol requirement. Proving this factual condition will be a critical hurdle for the Plaintiff.
- Technical Questions: The dispute may turn on whether the frame structures used in the 802.11ac standard, as implemented by Apple, meet all limitations of the claimed method. A defendant could argue that standard-compliant frames do not map to the specific "first section" / "second section" structure claimed or do not satisfy the "denser" pilot symbol limitation.
V. Key Claim Terms for Construction
’204 Patent: "compressing the estimated CSI" (Claim 1)
- The Term: "compressing the estimated CSI"
- Context and Importance: This term is at the heart of the invention. The infringement analysis depends entirely on whether Apple's method for reducing the amount of CSI data sent as feedback qualifies as "compressing" as envisioned by the patent. Practitioners may focus on this term because its scope will determine if standardized, widely used techniques fall within the patent's reach.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification summary describes the invention broadly as "compressing the estimated CSI; and sending the compressed CSI as the feedback" without limiting the mechanism (’204 Patent, col. 2:54-57). This could support an interpretation covering any method that reduces the data size of the CSI.
- Evidence for a Narrower Interpretation: The detailed embodiments focus on specific compression techniques, such as using a least squares method to generate parameters for a line or curve that fits the channel tap magnitudes (’204 Patent, col. 4:52-56) or applying a discrete cosine transform (DCT) to generate a spectrum from which significant parameters are selected (’204 Patent, col. 7:7-13). This may support a narrower construction limited to these or similar parameter-generation techniques.
’096 Patent: "pilot symbols that are denser" (Claim 8)
- The Term: "pilot symbols that are denser"
- Context and Importance: This is a precise, potentially dispositive limitation. Infringement of claim 8 requires factual proof that the accused "VHT format" uses a denser pilot symbol structure than the "legacy format." The construction of "denser" will define the evidentiary burden. Practitioners may focus on this term because it presents a clear, factual question that could resolve the infringement issue for this patent.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent does not appear to provide an explicit definition, suggesting the term should be given its plain and ordinary meaning. This could be interpreted broadly to mean a higher number of pilot symbols per unit of time, per unit of frequency, or per time-frequency resource block.
- Evidence for a Narrower Interpretation: The specification discusses denser pilot placement in the context of achieving "better channel estimation accuracy" to support "high-mobility" environments (’096 Patent, col. 5:8-15). A defendant may argue that "denser" must be interpreted in light of this stated objective, potentially requiring a specific type of density (e.g., temporal density) that is suited for tracking fast-changing channels.
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement for all three patents. The inducement theory is based on Defendant designing the Accused Instrumentalities to operate in an infringing manner and encouraging such use through promotional literature and user manuals (Compl. ¶¶ 48-49, 56-57, 64-65). The contributory infringement theory alleges the products are especially made for infringing use and are not staple articles of commerce suitable for substantial noninfringing use because they are pre-configured to employ the patented methods (Compl. ¶¶ 50, 58, 66).
- Willful Infringement: The complaint alleges willful infringement for all three patents, asserting that Defendant had "actual knowledge" of the patents since "no later than September 26, 2018," and continued to infringe despite an "objectively high likelihood" that its actions constituted infringement (Compl. ¶¶ 51-52, 59-60, 67-68).
VII. Analyst’s Conclusion: Key Questions for the Case
- Impact of IPRs: The most critical issue in this case is the post-filing cancellation in IPR proceedings of the primary claims asserted from the '204 and '326 patents. A threshold question for the court will be whether any viable infringement case remains for these two patents, as the asserted independent claims (claim 1 of the '204 Patent and claim 1 of the '326 Patent) have been found unpatentable.
- Evidentiary Proof: For the surviving '096 patent, a key evidentiary question will be one of factual proof: can the Plaintiff provide technical evidence to demonstrate that the accused products' VHT communication mode utilizes a frame structure where the "pilot symbols are denser" than in the legacy mode, as strictly required by asserted claim 8?
- Standard vs. Patented Method: Should the case proceed on any claims, a central dispute will be one of technical scope: do the methods implemented in the accused products, which are based on industry standards like IEEE 802.11ac, perform the specific functions required by the patent claims, or do they represent distinct, non-infringing technical implementations?