Personal Web Tech LLC v. Mavenlink Inc

I. Executive Summary and Procedural Information

• Parties & Counsel:
  • Plaintiff: PersonalWeb Technologies, LLC (Texas) and Level 3 Communications, LLC (Delaware)
  • Defendant: Mavenlink, Inc. (Delaware)
  • Plaintiff’s Counsel: Farnan LLP; Stubbs Alderton & Markiles, LLP
• Case Identification: 1:18-cv-01143, D. Del., 08/01/2018
• Venue Allegations: Venue is alleged to be proper in the District of Delaware because the Defendant is a Delaware corporation and thus resides in the district.
• Core Dispute: Plaintiff alleges that Defendant’s website, "mavenlink.com", infringes four patents related to identifying, managing, and controlling access to data in computer networks using content-based identifiers.
• Technical Context: The technology relates to content-addressable storage, where data files are identified by a unique value (a "fingerprint" or "hash") derived from their content, which is a foundational concept in cloud computing, content delivery networks (CDNs), and distributed data systems.
• Key Procedural History: The complaint notes that Plaintiff PersonalWeb has previously enforced the patents-in-suit against third parties, resulting in settlements and non-exclusive licenses.

Case Timeline

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

U.S. Patent No. 6,928,442 - "Enforcement and Policing of Licensed Content Using Content-Based Identifiers"

• Patent Identification: U.S. Patent No. 6,928,442, "Enforcement and Policing of Licensed Content Using Content-Based Identifiers," issued August 9, 2005 (the "’442 Patent").

The Invention Explained

• Problem Addressed: In networked computer systems, traditional methods of identifying data by name and location (e.g., pathnames) are inefficient and unreliable, as the same data can have different names and different data can have the same name, leading to data duplication and difficulty in verifying data integrity (Compl. ¶¶12-13; ’442 Patent, col. 2:13-25).
• The Patented Solution: The invention proposes replacing conventional naming with "substantially unique" identifiers, called "True Names," that are generated by applying a cryptographic hash function (like MD5 or SHA) to the content of the data itself (Compl. ¶¶14-16). This creates a direct, verifiable link between a file's identifier and its content, allowing for efficient management, de-duplication, and access control across a distributed network, independent of the file's name or location (’442 Patent, col. 3:7-12). The system can use these True Names to check for unauthorized or unlicensed content across a network of computers (’442 Patent, Abstract).
• Technical Importance: This content-based identification approach provides a robust method for managing data in large-scale distributed systems, reducing storage and bandwidth requirements by preventing redundant data copies (Compl. ¶11).

Key Claims at a Glance

• The complaint asserts infringement of at least independent claim 10 (Compl. ¶50).
• Claim 10 is a method claim with the following essential elements:
  • Obtaining a name for a data file, where the name is based on a function of the data comprising the file's contents.
  • Using the name to determine whether a copy of the data file is present on at least one computer in a distributed system.
  • Determining whether a present copy of the data file is an "unauthorized copy or an unlicensed copy."
• The complaint also asserts dependent claim 11 (Compl. ¶50).

U.S. Patent No. 7,802,310 - "Controlling Access to Data in a Data Processing System"

• Patent Identification: U.S. Patent No. 7,802,310, "Controlling Access to Data in a Data Processing System," issued September 21, 2010 (the "’310 Patent").

The Invention Explained

• Problem Addressed: This patent addresses the same foundational problem as the ’442 Patent: the inefficiency of managing data in distributed systems using location-based names rather than content-based identifiers (Compl. ¶¶12-13; ’310 Patent, col. 1:21-2:45).
• The Patented Solution: The patent describes a system for controlling access to data items. A first computer receives a request from a second computer that includes a "content-dependent name" for a data item (generated by a hash function). In response, the first computer compares this name to a plurality of values to determine if access is authorized and, based on that determination, either allows or denies the second computer access to the data item (’310 Patent, Abstract). The system is designed to work in a peer-to-peer network environment (’310 Patent, col. 7:4-6).
• Technical Importance: This solution provides a systematic way to manage data access rights in a distributed network by leveraging content-based identifiers, which is more efficient than methods that rely on tracking file locations or user-defined names (Compl. ¶17).

Key Claims at a Glance

• The complaint asserts infringement of at least independent claim 69 (Compl. ¶58).
• Claim 69 is a system claim comprising hardware and software configured to:
  • Receive at a first computer, from a second computer, a request for a data item that includes a content-dependent name generated by a hash function of the item's contents.
  • In response, compare the content-dependent name to a plurality of values.
  • Determine if access is authorized or unauthorized based on whether the name corresponds to one of the values.
  • Allow the data item to be provided to the second computer if access is not determined to be unauthorized.

U.S. Patent No. 7,945,544 - "Similarity-Based Access Control of Data in a Data Processing System"

• Patent Identification: U.S. Patent No. 7,945,544, "Similarity-Based Access Control of Data in a Data Processing System," issued May 17, 2011 (the "’544 Patent").
• Technology Synopsis: The patent describes a method for creating a "digital key" for a file by first generating "part values" (e.g., hashes) for constituent parts of the file and then applying a second function to those part values. This hierarchical hashing allows for efficient comparison and database lookup. A search key, generated in the same manner, is matched against digital keys in a database to find corresponding file information.
• Asserted Claims: Independent claims 46 and 55, and dependent claims 48 and 52 are asserted (Compl. ¶65).
• Accused Features: The accused features include the generation of content-based "fingerprints" for asset files (the "first function"), which are then included in webpage file URIs. A content-based ETag for the entire webpage file is then generated based on the contents including these fingerprinted URIs (the "second function"). This ETag is used as a key for database lookups to control caching and content distribution (Compl. ¶¶67-72).

U.S. Patent No. 8,099,420 - "Accessing Data in a Data Processing System"

• Patent Identification: U.S. Patent No. 8,099,420, "Accessing Data in a Data Processing System," issued January 17, 2012 (the "’420 Patent").
• Technology Synopsis: The patent claims a system that determines content-dependent digital identifiers for data items. The system then uses these identifiers to selectively permit access to the data items by checking whether the identifier corresponds to an entry in one or more databases.
• Asserted Claims: Independent claim 166 and a number of dependent claims are asserted (Compl. ¶76).
• Accused Features: The accused system allegedly generates content-dependent "fingerprints" and ETags for webpage files. It then uses these identifiers in a system of conditional GET requests to check against ETag values in server databases, thereby selectively determining whether a requesting computer can access the cached content or must receive new content (Compl. ¶¶78-81).

III. The Accused Instrumentality

Product Identification

• The accused instrumentality is the system and method for operating the website located at "mavenlink.com" (Compl. ¶29).

Functionality and Market Context

• The complaint alleges the "mavenlink.com" website utilizes a system to control the distribution and caching of webpage content (Compl. ¶30). This system allegedly uses two types of content-based identifiers. First, it generates "fingerprints" from the content of asset files (e.g., images, scripts) and inserts these fingerprints into the filenames of the assets, thereby changing the asset's URI when its content changes (Compl. ¶¶32, 36-37). Second, it generates content-based "ETag" values for the main webpage files by applying a hash function to their contents (Compl. ¶¶31, 39).
• When a browser requests a webpage, it sends a conditional HTTP GET request including the ETag of its cached version in an "If-None-Match" header (Compl. ¶¶31, 41). An intermediate or origin server compares this ETag to its current ETag for the file. If they match, the server sends an HTTP 304 "Not Modified" response, authorizing the browser to use its cached version. If they do not match, the server sends an HTTP 200 response with the new webpage file and its new ETag (Compl. ¶¶45-46). This system allegedly reduces bandwidth by ensuring that only files whose content has changed are transmitted over the network (Compl. ¶34).
• No probative visual evidence provided in complaint.

IV. Analysis of Infringement Allegations

U.S. Patent No. 6,928,442 Infringement Allegations

• Identified Points of Contention:
  • Scope Questions: A central question may be whether the term "unauthorized copy or an unlicensed copy," as used in the patent, can be construed to cover a file that is merely outdated or stale, as is determined by an ETag mismatch in a web caching context. The patent's specification discusses "licensed users" and tracking for "licensing purposes," which may suggest a different scope than cache validation (’442 Patent, col. 8:52-56).
  • Technical Questions: What evidence does the complaint provide that an ETag mismatch functions as a determination of authorization or license status, rather than simply a determination of content freshness for caching efficiency? The complaint alleges this functional equivalence directly (Compl. ¶54).

U.S. Patent No. 7,802,310 Infringement Allegations

• Identified Points of Contention:
  • Scope Questions: As with the ’442 Patent, a key issue may be whether the system's determination of cache validity (based on a URI/fingerprint match) constitutes a determination of whether "access to the data item is authorized or unauthorized" in the sense contemplated by the patent.
  • Technical Questions: The complaint alleges that URIs including content-based "fingerprints" function as the claimed "content-dependent name" (Compl. ¶60). The dispute may focus on whether this specific implementation meets all limitations of the asserted claim.

V. Key Claim Terms for Construction

• Patent: ’442 Patent

  • The Term: "unauthorized copy or an unlicensed copy of the data file" (Claim 10).
  • Context and Importance: This term is the central point of the infringement allegation for this patent. The complaint’s theory hinges on equating an ETag mismatch with a determination that a cached file is "unauthorized." The definition of this phrase will be dispositive.
  • Intrinsic Evidence for a Broader Interpretation: The patent abstract states the system "may check one or more computers for unauthorized or unlicensed content," suggesting a general-purpose applicability beyond formal digital rights management.
  • Intrinsic Evidence for a Narrower Interpretation: The specification repeatedly refers to "licensed (or authorized) parties" and tracking for "licensing purposes," and the title refers to "Licensed Content." This context may support an interpretation requiring a formal licensing or rights management scheme, not just a cache-validation check (’442 Patent, Abstract; col. 8:55-56).

• Patent: ’310 Patent

  • The Term: "content-dependent name" (Claim 69).
  • Context and Importance: The infringement theory relies on the accused "fingerprints" inserted into URIs qualifying as this term. Practitioners may focus on this term because its scope will determine whether modern web caching techniques that embed hashes in filenames fall within the patent's claims.
  • Intrinsic Evidence for a Broader Interpretation: The specification defines the term broadly as a "substantially unique data identifier for a particular data item" derived from its content, and explicitly lists a "message digest function or a hash function" as the means of creation (’310 Patent, col. 6:8-13; col. 15:40-42). This language may support reading the term on any content-based hash.
  • Intrinsic Evidence for a Narrower Interpretation: The specification consistently refers to this identifier as a "True Name," a specific term of art within the patent family (’310 Patent, col. 6:9). A defendant might argue that "content-dependent name" should be limited to the specific "True Name" structures and generation methods detailed in the specification, potentially distinguishing them from the ETags or filename fingerprints used in the accused system.

VI. Other Allegations

The complaint alleges direct infringement pursuant to 35 U.S.C. § 271 and does not contain specific counts or factual allegations for indirect infringement (inducement or contributory) or willful infringement (Compl. ¶¶ 50, 58, 65, 76).

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

This case will likely depend on the resolution of two central questions, one of definitional scope and one of functional equivalence:

• A core issue will be one of definitional scope: can the patent terms "content-dependent name" or "True Name," which originate from a 1995 priority date, be construed to cover the ETags and content-based URI "fingerprints" used in modern web caching and content delivery systems?
• A key evidentiary question will be one of functional equivalence: does the accused system's technical process for validating cache freshness—determining if a browser's local file is outdated via an ETag or URI mismatch—perform the same function as the claimed methods of determining whether a file is an "unauthorized or unlicensed copy" or whether "access...is authorized or unauthorized"?