DCT
4:09-cv-04479
Speed Track Inc v. Amazon.com Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: SpeedTrack, Inc. (California)
- Defendant: Amazon.com, Inc. (Delaware / Washington)
- Plaintiff’s Counsel: Hennigan, Bennett & Dorman LLP
- Case Identification: 4:09-cv-04479, N.D. Cal., 09/23/2009
- Venue Allegations: Plaintiff asserts venue is proper in the Northern District of California because each of the twenty-three named defendants, including Amazon.com, Inc., conducts substantial business through interactive websites accessible in the district and has committed the alleged acts of infringement in the district.
- Core Dispute: Plaintiff alleges that the faceted search and filtering functionality on Defendants' e-commerce websites infringes a patent on a method for accessing computer data using dynamically filtered, non-hierarchical categories.
- Technical Context: The technology at issue, commonly known as faceted search or guided navigation, is a foundational component of modern e-commerce and large-scale database browsing, allowing users to progressively refine search results.
- Key Procedural History: The complaint alleges that Plaintiff provided Amazon.com with written notice of the patent and its infringement allegations on December 20, 2006, nearly three years prior to filing the lawsuit. Subsequent to the filing of the complaint, the asserted patent survived an ex parte reexamination, with a certificate issued on July 5, 2011, confirming the patentability of claims 1-4, 7, 11-14, 20, and 21.
Case Timeline
| Date | Event |
|---|---|
| 1992-11-23 | '360 Patent Priority Date |
| 1996-08-06 | '360 Patent Issue Date |
| 2006-12-20 | Plaintiff sends written notice to Amazon |
| 2009-09-23 | Complaint Filing Date |
| 2011-07-05 | '360 Patent Reexamination Certificate Issued |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 5,544,360 - "METHOD FOR ACCESSING COMPUTER FILES AND DATA, USING LINKED CATEGORIES ASSIGNED TO EACH DATA FILE RECORD ON ENTRY OF THE DATA FILE RECORD"
- Patent Identification: U.S. Patent No. 5,544,360, “METHOD FOR ACCESSING COMPUTER FILES AND DATA, USING LINKED CATEGORIES ASSIGNED TO EACH DATA FILE RECORD ON ENTRY OF THE DATA FILE RECORD,” issued August 6, 1996.
The Invention Explained
- Problem Addressed: The patent identifies the rigidity of traditional hierarchical file systems (i.e., nested folders) as a key problem. Such systems make it difficult to store and later retrieve a single file that could logically belong in multiple categories. (’360 Patent, col. 1:39-50). Furthermore, conventional keyword search methods are described as being prone to failure due to user error (e.g., mistyping) or the inability to recall precise terms. (’360 Patent, col. 3:9-20).
- The Patented Solution: The invention proposes a file access system where users assign one or more non-hierarchical "categories" to each file. To find files, a user selects from lists of these categories to build a search filter. (’360 Patent, col. 4:50-64). The system’s core innovation is that as a user selects a category, the interface automatically and dynamically disables or hides any remaining category choices that would result in zero matches, thereby guaranteeing that the user can never define a search that returns no results. (’360 Patent, col. 4:9-15; col. 12:21-31). This process is illustrated in the patent's user interface diagram. (’360 Patent, FIG. 5).
- Technical Importance: This "guided navigation" approach ensures that every user selection meaningfully refines the search results, preventing the "dead-end" searches common in less sophisticated systems. (’360 Patent, col. 4:5-9).
Key Claims at a Glance
- The complaint asserts independent claims 1, 7, and 20, along with various dependent claims, against Amazon (Compl. ¶30).
- Independent Claim 1 (Method):
- (a) initially creating a computer-based category description table with a plurality of category descriptions having no predefined hierarchical relationship;
- (b) creating a file information directory that links files to selected category descriptions from the table; and
- (c) creating a search filter where, for each category selected, there is a "guarantee" that at least one file entry matches the selected set of categories.
- Independent Claim 7 (Method):
- A method based on claim 1 for creating a search filter, which includes the steps of:
- (1) "disabling" category descriptions that, if added to the filter, would not match any file entries; and
- (2) accepting user input to select a category for the search filter.
- The complaint does not explicitly reserve the right to assert other claims, but standard practice allows for amending infringement contentions.
III. The Accused Instrumentality
Product Identification
- The website operating under the URL Amazon.com (Compl. ¶30).
Functionality and Market Context
- The complaint alleges that the accused website provides a search functionality that allows visitors to find products by "selecting pre-defined categories descriptive of the products" (Compl. ¶30). This describes the well-known faceted search interface common on e-commerce sites, where users refine product listings by selecting from filter categories such as brand, price, size, color, or other product-specific attributes.
- The complaint does not provide specific details on the operation of Amazon's filtering logic but alleges that the overall system infringes the ’360 Patent.
IV. Analysis of Infringement Allegations
The complaint provides only a conclusory allegation of infringement without mapping specific product features to claim elements. The following chart is an inferred summary based on the patent's teachings and the general allegations against the accused e-commerce website.
'360 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| (a) initially creating in the computer system a category description table containing a plurality of category descriptions...the category descriptions having no predefined hierarchical relationship... | Amazon's back-end database stores product attributes (e.g., "Brand," "Color," "Price Range") that function as non-hierarchical categories. | ¶30 | col. 5:2-11 |
| (b) thereafter creating in the computer system a file information directory comprising at least one entry corresponding to a file...and a set of category descriptions selected from the category description table... | Amazon’s product database associates each product record (a "file") with its various attributes (the "category descriptions"). | ¶30 | col. 5:16-24 |
| (c) thereafter creating in the computer system a search filter comprising a set of category descriptions, wherein for each category description in the search filter there is guaranteed to be at least one entry in the file information directory having a set of category descriptions matching the set of category descriptions of the search filter. | The website's filtering interface dynamically updates the available filter options as a user makes selections, thereby ensuring that a user cannot select a combination of filters that would yield zero results. The complaint's visual evidence shows a user interface with selectable category lists for filtering a display of items (Compl. ¶28, Ex. 1 at FIG. 5). | ¶30 | col. 10:22-31 |
Identified Points of Contention
- Scope Questions: A potential dispute is whether the patent’s claims, which describe a system for managing computer "files" and "documents," can be construed to cover a system for searching "product listings" in a commercial database. The definition of "file" and "category" in this context may be a central point of contention.
- Technical Questions: The core technical question is whether the accused Amazon website actually performs the dynamic "guarantee" and "disabling" functions required by claims 1 and 7, respectively. The case may turn on evidence of whether Amazon's filtering system merely executes new database queries with each click or if it employs a specific mechanism, as taught in the patent, to prospectively disable filter options that would lead to a null result set. The complaint does not provide this level of technical detail.
V. Key Claim Terms for Construction
The Term: "guaranteed to be at least one entry"
- Context and Importance: This limitation from claim 1(c) is central to the invention's stated purpose of preventing "dead-end" searches. The outcome of the infringement analysis for claim 1 likely hinges on the construction of this phrase and whether the accused system provides such a "guarantee." Practitioners may focus on this term because it appears to require more than a standard database query; it suggests a system-level constraint on the user's choices.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: A plaintiff may argue that any system that, in practice, prevents a user from selecting a zero-result filter combination meets this limitation, regardless of the underlying mechanism. The patent's summary states the invention "ensur[es] that the user defines a filter which will always find at least one file." (’360 Patent, col. 4:6-8).
- Evidence for a Narrower Interpretation: A defendant may argue that "guaranteed" requires the specific method described in the patent: dynamically evaluating and "disabling" potential category selections. The patent links this guarantee to the process where "categories which would find no data are automatically excluded as pick list possibilities." (’360 Patent, Abstract; col. 10:46-53).
The Term: "disabling category descriptions"
- Context and Importance: This term from independent claim 7 specifies the mechanism for achieving the "guarantee" of claim 1. Proving that the accused system "disables" options, rather than merely not displaying them, will be critical for the plaintiff's infringement case on this claim.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: A plaintiff could argue that "disabling" covers any method of making a category unselectable, including simply omitting it from the list of available filters after a user makes a selection.
- Evidence for a Narrower Interpretation: A defendant could argue that the term requires an explicit change in the state of a visible user interface element. The specification suggests this by noting that disabled selections could be "shown as 'grayed'." (’360 Patent, col. 10:52-53). This implies the user is shown an option but is prevented from selecting it, which may be technically distinct from a system that simply regenerates a list of only valid options.
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement. The inducement theory is that Amazon actively encourages its website visitors to use the patented search method (Compl. ¶31). The contributory infringement theory is that Amazon provides the website software, knowing it to be especially adapted for infringement and not a staple article of commerce (Compl. ¶32).
- Willful Infringement: The complaint alleges willful infringement based on pre-suit knowledge. Plaintiff claims it sent written notice of the patent and the infringement allegations to Amazon on December 20, 2006, creating a basis for enhanced damages if infringement is found (Compl. ¶34, ¶35).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of definitional scope: can claim terms like "file" and "category description", which are described in the patent in the context of personal computer document management, be construed to read on product data and attributes within a large-scale, web-based e-commerce platform?
- A key evidentiary question will be one of functional operation: can the plaintiff produce evidence that Amazon’s filtering system performs the specific, proactive function of "disabling" search options to "guarantee" a non-empty result set, as required by the claims, or does it operate as a conventional database query system that is technically distinct from the patented method?
- The final outcome may also depend on validity challenges: while the patent survived reexamination, defendants will likely argue that the asserted claims, even if read broadly enough to cover the accused websites, are invalid as anticipated or obvious in light of prior art in the fields of database management and user interface design preceding the 1992 priority date.