DCT
1:19-cv-00994
Smart Locking Tech LLC v. Schlage Lock Co LLC
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Smart Locking Technologies LLC (Delaware)
- Defendant: Schlage Lock Company LLC (Delaware)
- Plaintiff’s Counsel: STAMOULIS & WEINBLATT LLC
- Case Identification: 1:19-cv-00994, D. Del., 05/29/2019
- Venue Allegations: Plaintiff alleges venue is proper in the District of Delaware because Defendant conducts substantial business in the district, where at least a portion of the alleged infringement occurred, and derives substantial revenue from goods and services provided there.
- Core Dispute: Plaintiff alleges that Defendant’s Schlage Encode line of smart locks infringes two patents related to locking mechanisms that utilize remotely issued, non-permanent access codes.
- Technical Context: The technology concerns networked electronic door locks that grant temporary access credentials via a remote server, a key enabling technology for the smart home, property management, and unattended delivery markets.
- Key Procedural History: The complaint does not mention prior litigation or administrative proceedings. U.S. Patent No. 6,696,918 is a continuation-in-part of the application that matured into U.S. Patent No. 6,300,873 and was issued subject to a terminal disclaimer over the '873 patent, which may suggest a close relationship in patentable subject matter between the two.
Case Timeline
| Date | Event |
|---|---|
| 1999-09-16 | Priority Date for '873 and '918 Patents |
| 2001-10-09 | Issue Date for U.S. Patent No. 6,300,873 |
| 2004-02-24 | Issue Date for U.S. Patent No. 6,696,918 |
| 2019-05-29 | Complaint Filed |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 6,696,918 - Locking Mechanism for Use with Non-Permanent Access Code (issued Feb. 24, 2004)
The Invention Explained
- Problem Addressed: The patent identifies the security risks and management burdens associated with static, reusable access codes for secure containers, particularly in the context of commercial deliveries. If a static code is compromised, a property remains vulnerable until the owner manually reprograms the lock ('918 Patent, col. 1:47-64).
- The Patented Solution: The invention discloses a system where a remote server issues non-permanent access codes to a locking mechanism. These codes can be for temporary or limited use, and the server handles the key management tasks, freeing the lock owner from that responsibility and enhancing security by ensuring codes expire ('918 Patent, Abstract; col. 2:8-21). The system architecture involves communication between the lock and the server to facilitate code issuance and tracking ('918 Patent, Fig. 3).
- Technical Importance: This technology provided a framework for centralizing the management of temporary digital keys for physical access, a critical step in enabling secure, large-scale, unattended services like package delivery for e-commerce ('918 Patent, col. 2:11-16).
Key Claims at a Glance
- The complaint asserts independent claim 32 (Compl. ¶11).
- The essential elements of claim 32 are:
- An actuator configured to unlock in response to entry of an authorized access code;
- An access code entry unit configured to accept a non-permanent use access code issued by a remote server, where the code has embedded information (e.g., vendor or package codes) to identify who or what accessed the lock;
- A locking mechanism controller programmed to transmit a message to a server or user indicating that a non-permanent code has been accepted.
- The complaint does not explicitly reserve the right to assert dependent claims.
U.S. Patent No. 6,300,873 - Locking Mechanism for Use with One-Time Access Code (issued Oct. 9, 2001)
The Invention Explained
- Problem Addressed: The patent addresses the same problem as its continuation-in-part: the insecurity of static vendor codes for storage devices, which, once learned by an unauthorized party, grant persistent access ('873 Patent, col. 1:46-54).
- The Patented Solution: The invention describes a server-based system for issuing one-time use access codes. A central server maintains lists of valid codes for each lock, issues a unique code upon request from an authorized entity like a merchant, and updates the list to invalidate the code after its use or expiration. A key aspect of the solution is the generation of these codes using a "cryptographically strong random number generator" to ensure their security ('873 Patent, Abstract; col. 2:21-34).
- Technical Importance: This system represents an early model for a third-party service managing single-use digital credentials for physical assets, laying the groundwork for secure access control in the context of growing e-commerce and delivery services ('873 Patent, col. 2:8-12).
Key Claims at a Glance
- The complaint asserts independent claim 36 (Compl. ¶21).
- The essential elements of claim 36 are:
- An actuator configured to unlock in response to entry of an authorized access code; and
- An access code entry unit configured to accept a one-time use access code issued by a remote server, where the code comprises a number generated by a cryptographically strong random number generator.
- The complaint does not explicitly reserve the right to assert dependent claims.
III. The Accused Instrumentality
Product Identification
- The Schlage Encode WiFi Deadbolt ("Encode") (Compl. ¶11).
Functionality and Market Context
- The complaint alleges the Encode is a smart deadbolt with integrated Wi-Fi, allowing it to connect directly to a home's network without an additional hub (Compl. ¶14, p.3 visual). A screenshot from Defendant's website describes how the lock pairs with the Schlage Home app to grant access with customized codes (Compl. ¶14, p.3 visual).
- Functionally, it allows users to create and manage up to 100 access codes that can be set for "recurring, temporary or permanent access" (Compl. ¶14, p.3 visual). The complaint includes a screenshot from a promotional video showing the app interface for creating scheduled access for specific days and times (Compl. ¶13, p.13 visual).
- The system is alleged to provide notifications to the user's smartphone when an access code is used and to maintain an "activity log" that tracks usage, identifying which code was used for access (Compl. ¶18; ¶17). A screenshot of such a notification reads "Access code Beth unlocked Front Door" (Compl. p.14 visual). The complaint alleges these features position the product as a comprehensive remote access control solution for homeowners (Compl. ¶14, p.3 visual).
IV. Analysis of Infringement Allegations
U.S. Patent No. 6,696,918 Infringement Allegations
| Claim Element (from Independent Claim 32) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| an actuator configured to unlock in response to entry of an authorized access code; | The complaint alleges the Encode product contains an internal actuator that operates the lock mechanism upon entry of a valid code, citing a parts diagram from the product's Quick Start Guide that identifies the bolt and internal assembly (Compl. p.4 visual). | ¶15 | col. 12:59-62 |
| an access code entry unit configured to accept a non-permanent use access code issued by a remote server, the access code having an embedded vendor code(s), and/or a package code(s), and/or other identification information to identify goods and/or who/what accessed the locking mechanism; | The complaint alleges the Encode's touchscreen and associated app functionality act as an access code entry unit that accepts temporary codes (Compl. ¶16). It further alleges that the user-assigned names for codes (e.g., "Housekeeper") constitute "identification information" that indicates who accessed the lock, as shown in an "Activity Log" screenshot (Compl. p.11 visual). | ¶16-17 | col. 8:55-65 |
| a locking mechanism controller programmed to transmit a message to a server and/or user indicating a non-permanent use access code has been accepted. | The complaint alleges the Encode lock sends notifications to the user's smartphone via the Schlage Home app when a code is used (Compl. ¶18). This is supported by screenshots of the app's notification settings and a push notification message on a phone's lock screen (Compl. pp.13-14 visuals). | ¶18 | col. 15:45-54 |
- Identified Points of Contention:
- Technical Questions: A central question will be whether a user-assigned name (e.g., "Beth," "Housekeeper") in the Schlage app qualifies as "embedded... identification information" under the patent's claim language.
- Scope Questions: The infringement analysis may turn on the scope of "non-permanent use access code." Does a code set for "recurring" access, as described in Schlage's marketing materials (Compl. ¶14), fall within the meaning of "non-permanent" as contemplated by the patent?
U.S. Patent No. 6,300,873 Infringement Allegations
| Claim Element (from Independent Claim 36) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| an actuator configured to unlock in response to entry of an authorized access code; and | As with the '918 patent, the complaint alleges the Encode product includes an actuator to unlock the deadbolt, referencing the product's parts diagram (Compl. p.17 visual). | ¶25 | col. 11:8-10 |
| an access code entry unit configured to accept a one-time use access-code issued by a remote server, wherein the one-time use access code comprises a number generated by a cryptographically strong random number generator. | The complaint alleges the Encode's keypad and app accept "one-time use" codes issued by a remote server (Compl. ¶26). It further alleges, "upon information and belief," that these codes are generated by a "cryptographically strong random number generator" (Compl. ¶27). The complaint cites marketing material that describes scheduling codes for a "single day" as support for the "one-time use" capability (Compl. p.24 visual). | ¶26-27 | col. 2:30-34 |
- Identified Points of Contention:
- Technical Questions: The complaint asserts that the access codes are generated by a "cryptographically strong random number generator" on the basis of "information and belief" (Compl. ¶27) but provides no direct technical evidence. A key point of dispute will be whether the algorithm used by the Schlage system meets the technical standard of "cryptographically strong."
- Scope Questions: What evidence will be required to prove that a code scheduled for a "single day" (Compl. p.24 visual) constitutes a "one-time use" code as required by the claim, which could be interpreted as expiring after a single entry rather than over a 24-hour period?
V. Key Claim Terms for Construction
Term: "cryptographically strong random number generator" ('873 Patent, Claim 36)
- Context and Importance: The infringement allegation for the '873 patent hinges entirely on this technical limitation. Practitioners may focus on this term because the complaint offers no factual support for how the accused product's codes are generated, making it a likely area for a dispositive summary judgment motion if discovery does not produce sufficient evidence.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent does not define the term or specify a particular algorithm, which a party could argue leaves its precise technical requirements open to a more flexible interpretation based on the overall context of providing secure, non-reusable codes.
- Evidence for a Narrower Interpretation: A party could argue that in the absence of a specific definition in the patent, the term should be given its established technical meaning in the field of computer science, which implies specific properties of unpredictability and statistical randomness that a simple number generator might not possess. The abstract and summary both use this exact phrase, suggesting it is a deliberate and important limitation ('873 Patent, Abstract; col. 2:32-34).
Term: "identification information to identify ... who/what accessed the locking mechanism" ('918 Patent, Claim 32)
- Context and Importance: The plaintiff's infringement theory relies on user-created labels like "Housekeeper" meeting this definition. The defendant may argue that this term requires more structured data, such as a formal vendor ID or package tracking number as exemplified in the claim itself.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The plain language "who/what accessed" is expansive and could reasonably include a human-readable name assigned to a code for the express purpose of tracking who is using it. The patent discusses tracking "which individuals/entities had valid access codes" ('918 Patent, col. 9:41-43).
- Evidence for a Narrower Interpretation: The claim lists "vendor code(s)" and "package code(s)" as examples. A party could argue that under the ejusdem generis canon of construction, the general phrase "other identification information" should be limited to the same class as the specific examples—namely, commercially generated, formal identifiers. The specification's description of a confirmation message notes it can indicate "who/which organization made the delivery" ('918 Patent, col. 15:52-54), which may support a more commercial interpretation.
VI. Other Allegations
- Indirect Infringement: The complaint's prayer for relief seeks a judgment that Defendant has induced infringement of both patents (Compl. p.25). The factual basis for this appears to be allegations that Defendant provides the Encode product along with its companion mobile application and instructions, which together allegedly direct and encourage end-users to operate the system in a manner that directly infringes the patent claims (Compl. ¶11, ¶16, ¶18).
- Willful Infringement: The complaint does not contain a formal count for willful infringement. However, the prayer for relief requests a declaration that the case is "exceptional" under 35 U.S.C. § 285, the statutory basis for awarding attorney's fees in cases of willful infringement or other litigation misconduct (Compl. p.25). The complaint does not allege that Defendant had knowledge of the patents prior to the lawsuit.
VII. Analyst’s Conclusion: Key Questions for the Case
This case appears to present focused questions of both technical evidence and claim construction. The key issues for the court will likely be:
- An evidentiary question of technical operation: Can the plaintiff produce evidence through discovery to prove its "information and belief" allegation that the Schlage Encode system uses a "cryptographically strong random number generator"? The viability of the infringement claim on the '873 patent depends almost entirely on the answer.
- A question of definitional scope: Will the term "identification information," in the context of the '918 patent, be construed broadly enough to read on user-assigned text labels in an app, or will the court limit its meaning to more formal, system-generated data like the "vendor codes" and "package codes" listed as examples in the claim?
- A question of functional correspondence: Does the accused product's ability to create "temporary" or "single day" codes meet the "non-permanent use" and "one-time use" limitations of the patents, which were drafted in the context of single-entry commercial deliveries? The court will need to determine if there is a functional match or a fundamental difference in operation.