DCT
1:17-cv-00283
Blackbird Tech LLC v. Cloudflare Inc
Key Events
Complaint
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Blackbird Tech LLC d/b/a Blackbird Technologies (Delaware LLC, PPOB Massachusetts)
- Defendant: Cloudflare, Inc. (Delaware)
- Plaintiff’s Counsel: Stamoulis & Weinblatt LLC
- Case Identification: 1:17-cv-00283, D. Del., 03/16/2017
- Venue Allegations: Venue is alleged to be proper as Defendant is a Delaware corporation that transacts business and has allegedly committed acts of infringement within the District of Delaware.
- Core Dispute: Plaintiff alleges that Defendant’s Content Delivery Network (CDN) services infringe a patent related to methods and systems for intercepting client-server communications to insert third-party data.
- Technical Context: The technology concerns network architecture for content delivery, specifically modifying data streams between a user (client) and a web content host (origin server) to provide alternative or enhanced content.
- Key Procedural History: The complaint does not mention any prior litigation, Inter Partes Review (IPR) proceedings, or licensing history related to the patent-in-suit.
Case Timeline
| Date | Event |
|---|---|
| 1998-07-21 | ’335 Patent Priority Date |
| 2002-09-17 | ’335 Patent Issue Date |
| 2017-03-16 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 6,453,335 - "Providing an Internet Third Party Data Channel"
- Patent Identification: U.S. Patent No. 6,453,335, "Providing an Internet Third Party Data Channel," issued September 17, 2002.
The Invention Explained
- Problem Addressed: The patent describes a limitation in the then-prevalent "two party communication" paradigm of the internet, where a direct logical connection exists between a client and a server. This structure makes it "difficult to incorporate third party data into an existing data channel," such as value-added information from a portal service, once a user navigates away from the portal's website (Compl. ¶10; ’335 Patent, col. 1:45-51).
- The Patented Solution: The invention proposes inserting a "processing device" logically between the client and server to monitor their communications (’335 Patent, Fig. 1). This device inspects the data stream for a "predetermined property," like an HTTP error status code (e.g., "404 Not Found"). Upon detecting this trigger, the device accesses a separate "data source," retrieves "third party data," and then modifies or replaces the original server response before forwarding a "resultant data communication" to the user (Compl. ¶11; ’335 Patent, col. 5:26-36). For instance, it could replace a standard error page with a custom, more helpful page from a portal service (’335 Patent, col. 6:3-11).
- Technical Importance: This approach was designed to enhance the flexibility of data distribution on the internet, allowing third-party services to inject contextually relevant information into a user's browsing session without requiring new client or server software (’335 Patent, col. 2:23-30).
Key Claims at a Glance
- The complaint asserts dependent claims 8 and 24, which are based on independent claims 1 (method) and 18 (apparatus), respectively (Compl. ¶13).
- Independent Claim 1 (Method) requires:
- Using a "processing device distinct from said internet server" to monitor a data channel.
- Monitoring for a "data communication having a predetermined property."
- Upon detection, accessing a "data source" to get "third party data."
- Modifying or replacing the original data communication with the third-party data to create a "resultant data communication."
- Sending the resultant data to the intended recipient.
- Independent Claim 18 (Apparatus) recites a corresponding system with a "processing device" adapted to perform the functions of the method in Claim 1.
- Asserted dependent claims 8 and 24 add the key limitation that "data is only transmitted on said third party data channel when the data transmission rate of said server to said client is below a predetermined threshold."
- The complaint does not explicitly reserve the right to assert other claims.
III. The Accused Instrumentality
Product Identification
- Defendant’s Content Delivery Network ("CDN") systems and services (Compl. ¶13).
Functionality and Market Context
- The complaint describes the Cloudflare CDN as a network of data centers, also called "points of presence" or "edge servers," that are located logically and physically between end-users ("user systems") and its customers' websites ("origin servers") (Compl. ¶15).
- A primary function is to cache copies of content from the origin servers. When a user requests content, Cloudflare's edge servers can deliver it from the cache without contacting the origin server, reducing load and improving speed (Compl. ¶16).
- The complaint alleges that when the Cloudflare CDN detects certain communications from an origin server, such as an HTTP status code indicating an error, its systems intercept this communication. Instead of passing the error to the user, the CDN accesses its own cache to retrieve a customized or "branded" error webpage and delivers that page to the user (Compl. ¶¶18, 20). No probative visual evidence provided in complaint.
IV. Analysis of Infringement Allegations
The infringement theory posits that Cloudflare’s CDN architecture and its method of handling server errors map onto the elements of the asserted claims.
’335 Patent Infringement Allegations (based on method Claim 1/8)
| Claim Element (from Independent Claim 1 & Dependent Claim 8) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| using a processing device distinct from said internet server for monitoring said existing data channel for a data communication having a predetermined property | Cloudflare’s CDN data centers are distinct from its customers' origin servers and monitor communications for properties like HTTP error status codes. | ¶¶15, 17, 18 | col. 7:11-19 |
| upon detection..., accessing said data source to obtain third party data | Upon detecting an error code, Cloudflare’s processing devices access the local CDN cache (the "data source") to retrieve a custom error webpage. | ¶¶19, 20 | col. 5:26-29 |
| a step selected from the group consisting of... replacing said data communication in response to said third party data to obtain a resultant data communication | Cloudflare’s CDN replaces the origin server’s error message with the custom error webpage retrieved from its cache. | ¶¶19, 20 | col. 5:29-34 |
| sending said resultant data communication to said intended recipient | Cloudflare’s data centers send the custom error page to the user's system. | ¶19 | col. 5:34-36 |
| wherein data is only transmitted on said third party data channel when the data transmission rate of said server to said client is below a predetermined threshold | The complaint alleges that custom error pages are served in response to error codes that indicate an issue with the origin server's transmission rate. | ¶¶21, 22 | col. 4:61-65 |
Note: The allegations for apparatus claim 24 are substantively identical, framing the CDN components as the "apparatus" performing these functions.
Identified Points of Contention
- Scope Questions: The dispute may turn on whether a customer's own pre-configured, branded error page, stored on Cloudflare's servers, constitutes "third party data" from a "data source distinct from said internet server." The patent's examples focus on data from external entities like portal services (’335 Patent, col. 2:33-38), raising the question of whether content originating from the same entity as the origin server (the website owner) but stored on an intermediary cache qualifies.
- Technical Questions: The complaint alleges that serving a custom error page satisfies the "low transmission rate" limitation, asserting that server errors are indicative of such a condition (Compl. ¶22). A central technical question will be what evidence demonstrates that the accused system's trigger is specifically a "data transmission rate... below a predetermined threshold," as claimed, rather than simply a categorical response to an HTTP status code, irrespective of the actual transmission rate or server load.
V. Key Claim Terms for Construction
"third party data"
- Context and Importance: The definition of this term is critical. If construed narrowly to mean data originating from a commercial entity unaffiliated with the primary client-server transaction, Cloudflare may argue that serving a customer's own branded error page does not meet this limitation. If construed broadly to mean any data from a source other than the origin server's primary response, the plaintiff's theory may be supported.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification suggests the data could be a simple "technical explanation of the error, or a translation of the reason phrase" (’335 Patent, col. 6:9-12), which does not inherently require a different commercial entity.
- Evidence for a Narrower Interpretation: The patent’s background and summary repeatedly frame the invention’s purpose around "portal services" and inserting data from an "internet service provider or any other entity forwarding internet traffic" (’335 Patent, col. 2:26-38), which suggests data from an entity external to the client and server owner.
"when the data transmission rate of said server to said client is below a predetermined threshold"
- Context and Importance: This limitation appears in both asserted dependent claims (8 and 24) and is a key infringement hurdle. The case may depend on whether an HTTP error code is, by itself, sufficient to meet this "low transmission rate" condition.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: A party could argue that a server error (e.g., 404 or 5xx) inherently represents a transmission rate of or near zero, thereby falling below any reasonable "predetermined threshold." The complaint appears to advance this theory (Compl. ¶22).
- Evidence for a Narrower Interpretation: The specification describes this feature in the context of network efficiency, stating it is "preferred to use the third party data channel only when the transmission load originating from the server is low. Thus the efficiency of the user's internet connection can be increased" (’335 Patent, col. 4:61-65). This language suggests a condition related to managing available bandwidth, not necessarily a binary response to a server failure state.
VI. Other Allegations
Willful Infringement
- The complaint does not contain a specific count for willful infringement or allege pre-suit knowledge of the patent. However, the prayer for relief requests that the case be found "exceptional under 35 U.S.C. § 285" and seeks an award of "enhanced damages" (Compl., Prayer for Relief D), which is the relief typically associated with a finding of willful or egregious infringement.
VII. Analyst’s Conclusion: Key Questions for the Case
A core issue will be one of definitional scope: Can the term "third party data," which the patent repeatedly associates with external entities like "portal services," be construed to cover a website owner's own branded content (e.g., a custom error page) that is cached and served by an intermediary CDN?
A key evidentiary question will be one of technical causation: Does the complaint's allegation—that responding to a server error is equivalent to detecting that the "data transmission rate... is below a predetermined threshold"—align with the technical reality of the accused CDN and the patent's description of this feature as a means of improving network efficiency? The court will need to determine if an error state inherently satisfies this specific claim limitation.