DCT
2:19-cv-00025
Rembrandt Wireless Tech LP v. Apple Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Rembrandt Wireless Technologies, LP (Virginia)
- Defendant: Apple Inc. (California)
- Plaintiff’s Counsel: Heim, Payne & Chorush, L.L.P.; Ahmad, Zavitsanos, Anaipakos, Alavi & Mensing, P.C.; Ward & Smith Law Firm
- Case Identification: 2:19-cv-00025, E.D. Tex., 01/24/2019
- Venue Allegations: Plaintiff alleges venue is proper in the Eastern District of Texas because Defendant maintains regular and established places of business, including Apple Stores, within the district and has committed acts of infringement there. Plaintiff also notes the court's prior experience with the patents-in-suit as a matter of judicial economy.
- Core Dispute: Plaintiff alleges that Defendant’s products incorporating Bluetooth Enhanced Data Rate (EDR) functionality infringe two patents related to systems for communicating using at least two different modulation methods.
- Technical Context: The technology concerns methods for allowing devices in a master-slave network to communicate using multiple, otherwise incompatible modulation schemes, which is relevant for standards like Bluetooth that support both a basic, lower-speed mode and an enhanced, higher-speed mode.
- Key Procedural History: The complaint states that the patents-in-suit were previously asserted against Samsung in the same district. That litigation reportedly resulted in a jury verdict of validity and infringement, which was affirmed by the U.S. Court of Appeals for the Federal Circuit. The complaint also notes that the USPTO denied institution of inter partes reviews and confirmed the validity of the asserted claims in ex parte reexamination proceedings.
Case Timeline
| Date | Event |
|---|---|
| 1997-12-05 | Priority Date for ’228 and ’580 Patents |
| 2011-09-20 | U.S. Patent No. 8,023,580 Issued |
| 2013-06-04 | U.S. Patent No. 8,457,228 Issued |
| 2014-12-04 | Plaintiff disclaimed certain claims of ’580 Patent |
| 2018-08-27 | Samsung became licensed to the patents-in-suit |
| 2019-01-24 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,457,228, "System and Method of Communication Using at Least Two Modulation Methods," Issued June 4, 2013
The Invention Explained
- Problem Addressed: Prior art communication systems, particularly in a master-slave network, required all devices to use a single, common modulation method (Compl. ¶10; ’228 Patent, col. 1:29-35). This was inefficient when a network included devices with diverse needs, such as some requiring high-speed data transfer and others only needing low-speed communication, as it forced all devices to use expensive, high-performance modems even for low-rate tasks (’228 Patent, col. 2:1-15).
- The Patented Solution: The invention describes a master device capable of communicating with different types of slave devices using different modulation methods on the same network (’228 Patent, col. 2:19-23). The master can transmit a message that begins with a first part using a primary modulation method (e.g., Type A), which includes information indicating an impending switch to a secondary modulation method (e.g., Type B) for a subsequent part of the message containing the data payload (’228 Patent, col. 6:27-36, Fig. 5). This allows a master to seamlessly communicate with both "Type A" and "Type B" slaves without having to tear down and re-establish the communication session.
- Technical Importance: This approach allows for backward compatibility and greater efficiency in networks where devices with different capabilities and cost points must coexist (Compl. ¶20; ’228 Patent, col. 3:9-14).
Key Claims at a Glance
- The complaint asserts independent claim 21 (Compl. ¶28).
- Claim 21 is directed to a master communication device configured to transmit messages in a master-slave network. Its essential elements include:
- A "first message" comprising "first information" and "second information," both modulated according to a "first modulation method."
- A "second message" comprising "third information" modulated by the "first modulation method" and "fourth information" modulated by a "second modulation method."
- The "third information" indicates an "impending change" to the "second modulation method."
- The "fourth information" is transmitted after the "third information" and comprises data for a single slave transceiver.
- The complaint does not explicitly reserve the right to assert dependent claims.
U.S. Patent No. 8,023,580, "System and Method of Communication Using at Least Two Modulation Methods," Issued September 20, 2011
The Invention Explained
- Problem Addressed: The ’580 Patent shares its specification with the ’228 Patent and thus addresses the same problem of enabling communication in a network with devices that use incompatible modulation methods (Compl. ¶35; ’580 Patent, col. 2:16-22).
- The Patented Solution: The solution is substantively identical to that of the ’228 Patent: a master device that can switch modulation methods within a single communication transmission to talk to different types of slave devices (’580 Patent, Abstract). The master sends discrete transmissions structured with a first portion that can indicate an impending change to a second modulation method used for the payload portion (’580 Patent, Abstract). The complaint visualizes this concept using Figure 8 from the patent, showing a communication (172) where a training signal uses a first modulation method to notify of a change to a second modulation method for the subsequent data signal (Compl. ¶15, Annotated FIG. 8).
- Technical Importance: This system provides for seamless communication between legacy and newer devices, increasing network efficiency and reducing costs by avoiding the need for universal high-performance modems (’580 Patent, col. 2:1-15, col. 3:9-14).
Key Claims at a Glance
- The complaint asserts independent claims 2 and 59 (Compl. ¶36).
- Claim 2 is directed to a device where a transceiver transmits a message with a "first sequence" and a "second sequence," where the first sequence indicates which modulation method will be used for the second sequence.
- Claim 59 is directed to a communication device with a transceiver, where its essential elements include:
- Transmitting messages with a "first sequence" in a "first modulation method."
- The "first sequence" indicates which of the "first modulation method" or a "second modulation method" is used for a "second sequence."
- In at least one message, the "first sequence" indicates an "impending change" from the first to the second modulation method.
- The "second sequence" is then modulated using the "second modulation method" and transmitted after the "first sequence."
- The complaint does not explicitly reserve the right to assert dependent claims.
III. The Accused Instrumentality
Product Identification
A broad range of Apple products are accused, including iPhones, iPads, MacBooks, AirPods, and Apple Watches, collectively referred to as "Apple Bluetooth EDR Products." These are products that support Bluetooth specifications incorporating Enhanced Data Rate (EDR) (Compl. ¶¶28-29).
Functionality and Market Context
The complaint alleges that the accused products operate in a master-slave relationship and can transmit using at least two different modulation methods (Compl. ¶¶30, 37). Specifically, the functionality relies on the Bluetooth standard's use of (1) Gaussian Frequency Shift Keying (GFSK) for Basic Rate (BR) packets and (2) Differential Phase Shift Keying (DPSK) for Enhanced Data Rate (EDR) packets (Compl. ¶¶30, 37). The complaint alleges that an EDR packet comprises a GFSK-modulated header and a DPSK-modulated payload, which maps onto the claimed invention (Compl. ¶30). The complaint does not detail the products' market positioning beyond noting that Samsung, a prior licensee, is Apple's "biggest competitor" (Compl. ¶31).
IV. Analysis of Infringement Allegations
’228 Patent Infringement Allegations
| Claim Element (from Independent Claim 21) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a master communication device configured to communicate with one or more slave transceivers according to a master/slave relationship | Each Apple Bluetooth EDR Product can operate as a master in a master-slave relationship with other Bluetooth devices. | ¶30 | col. 8:17-23 |
| transmit a "first message" ... compris[ing] first information modulated according to a first modulation method, [and] second information ... modulated according to the first modulation method | The products transmit a Basic Rate packet, where both the access code/header and payload are modulated using GFSK (the "first" method). | ¶30 | col. 8:32-42 |
| transmit a "second message" ... compris[ing] third information modulated according to the first modulation method | The products transmit an Enhanced Rate packet, which begins with an access code/header modulated using GFSK. | ¶30 | col. 8:43-51 |
| wherein the third information comprises information that is indicative of an impending change in modulation to a second modulation method | The GFSK header of the EDR packet allegedly indicates the upcoming change to the DPSK payload. | ¶30 | col. 8:47-51 |
| and fourth information ... being modulated according to the second modulation method | The payload of the EDR packet is modulated using DPSK (the "second" method). | ¶30 | col. 8:52-56 |
’580 Patent Infringement Allegations
| Claim Element (from Independent Claim 59) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A communication device capable of communicating according to a master/slave relationship...comprising: a transceiver...configured to transmit messages with: a first sequence, in the first modulation method | Apple's Bluetooth EDR Products operate in a master-slave relationship and transmit messages containing a "first sequence" (a GFSK access code/header). | ¶37 | col. 12:50-61 |
| that indicates at least which of the first modulation method and the second modulation method is used for modulating a second sequence | The LT_ADDR and TYPE fields in the GFSK header indicate the modulation method of the subsequent payload ("second sequence"). | ¶37 | col. 12:62-65 |
| wherein, in at least one message, the first sequence indicates an impending change from the first modulation method to the second modulation method | The header of an Enhanced Rate packet, using GFSK, indicates the impending change to a DPSK payload. | ¶12:1-5 | |
| and the second sequence, modulated in accordance with the modulation method indicated by the first sequence and...modulated using the second modulation method, wherein the second sequence is transmitted after the first sequence | The payload of an Enhanced Rate packet is modulated using DPSK and follows the GFSK header. | ¶37 | col. 12:6-12 |
Identified Points of Contention
- Scope Questions: A central question will be whether a single, integrated Bluetooth EDR packet (comprising a header and payload) constitutes the distinct, sequentially described components of the claims (e.g., "third information" followed by "fourth information" in the '228 patent, or a "first sequence" followed by a "second sequence" in the '580 patent). The complaint's depiction of a communication with a distinct training signal and data signal (Compl. Annotated FIG. 8, seq. 172) may be contrasted with the more integrated structure of an actual Bluetooth packet.
- Technical Questions: The infringement theory hinges on the allegation that the GFSK-modulated header of a Bluetooth EDR packet performs the claimed function of "indicat[ing] an impending change" to the DPSK-modulated payload. A point of contention may be whether the header fields technically function as a notification of a change in modulation, as required by the claims, or simply as a standard packet descriptor that inherently precedes a payload of a known type. The complaint presents this mapping as fact, but the defense may argue a functional mismatch.
V. Key Claim Terms for Construction
The complaint does not explicitly identify terms for construction but heavily references prior litigation where terms were construed (Compl. ¶8, ¶42). The mapping of Bluetooth packets to the claim language raises questions about the following terms.
- The Term: "message" (in '228 Patent) and "sequence" (in '580 Patent).
- Context and Importance: Practitioners may focus on these terms because the entire infringement theory rests on mapping a single Bluetooth packet to multiple claimed "messages" or "sequences." For the '228 patent, the complaint alleges a Basic Rate packet is the "first message" and an Enhanced Rate packet is the "second message" (Compl. ¶30). The construction of "message" will determine if an EDR packet, with its header and payload, can be considered a single "second message" containing distinct "third" and "fourth" information components.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification describes the invention as providing "seamless communication" and uses terms like "transmission sequences" and "group of transmission sequences" generally, which could support reading the claims onto the components of a single, modern data packet ('580 Patent, col. 7:62-66).
- Evidence for a Narrower Interpretation: The patent figures, particularly the ladder diagrams like Figure 5, depict the claimed "sequences" (e.g., 106, 108) as distinct transmissions over time from the master device (’228 Patent, Fig. 5; Compl. ¶¶17-18). This could support a narrower interpretation requiring more temporal or structural separation between the claimed components than may exist within a single Bluetooth packet.
VI. Other Allegations
- Indirect Infringement: The complaint alleges active inducement by Apple. The basis for this claim includes selling the accused products, marketing their infringing capabilities, and providing instructions and technical support that encourage use of the Bluetooth EDR specifications (Compl. ¶31, ¶38).
- Willful Infringement: The willfulness allegation is based on both pre-suit and post-suit knowledge. Pre-suit knowledge is alleged to stem from Apple's awareness of the prior, successful litigation against its "biggest competitor," Samsung, involving the same patents and technology, as well as information potentially learned from shared vendors like Broadcom (Compl. ¶31, ¶38). Post-suit knowledge is based on the filing of the complaint (Compl. ¶33, ¶40).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of structural and functional mapping: Does the integrated architecture of a standard Bluetooth EDR packet, with its GFSK-modulated header and DPSK-modulated payload, meet the specific, sequentially-elemented "message" and "sequence" limitations of the asserted claims? Or do the claims, as supported by the specification's diagrams, require more distinct and separate transmissions?
- A second key issue will be the preclusive or persuasive effect of prior litigation: To what extent will the court be influenced by the prior claim construction, infringement verdict, and validity findings from the Samsung litigation, which was affirmed on appeal? While not legally binding against a new defendant (Apple), the extensive prior judicial and USPTO review of these specific patents and claims will be a significant factor in the proceedings.
- An evidentiary question will be one of intent and knowledge for willfulness: What evidence can Plaintiff produce to demonstrate that Apple had pre-suit knowledge of the patents and their alleged applicability to Bluetooth EDR, beyond general awareness of the Samsung litigation? The strength of the willfulness claim may depend on demonstrating specific knowledge rather than constructive notice.