Microsoft Corp v. Enfish LLC

1. Case Identification

• Case #: IPR2014-00574
• Patent #: 6,151,604
• Filed: April 3, 2014
• Petitioner(s): Microsoft Corporation
• Patent Owner(s): Enfish, LLC
• Challenged Claims: 1-2, 6-7, 11-13, 31-32, 36-37, and 41-43

2. Patent Overview

• Title: User-Adjustable Database System
• Brief Description: The ’604 patent discloses a database system built on a single, flexible, self-referential logical table. This architecture stores both data and schema information (definitions of columns) in the same table, which contrasts with conventional databases that use separate tables for data and schema.

3. Grounds for Unpatentability

Petitioner presented this "Second Petition" to address arguments and claim constructions advanced by the Patent Owner in parallel district court litigation after the filing of Petitioner's first IPR petition. Specifically, the Patent Owner argued for a narrow construction of "object identification numbers (OIDs)" that it alleged was not met by the primary prior art in the first petition. The grounds below add the Smith reference, which Petitioner argued explicitly discloses OIDs meeting this narrow construction, to streamline the proceedings.

Ground 1: Obviousness over Chang and Smith - Claims 1-2, 31-32 are obvious over Chang in view of Smith

• Prior Art Relied Upon: Chang (European Patent Application 03 36580 A2) and Smith (5,404,510).
• Core Argument for this Ground:
  • Prior Art Mapping: Petitioner argued that Chang, which describes a relational database system, discloses the base limitations of the independent claims. Chang teaches a database with system catalogs (e.g., SYS.TABLES, SYS.COLUMNS) that are themselves logical tables containing rows and columns. These catalogs store schema information, including rows that define the database's own tables and columns. This self-referential structure meets the core limitation of having a logical row that defines the columns of the table. To address the Patent Owner’s narrow interpretation of OIDs, Petitioner asserted that Smith explicitly discloses assigning unique “object ids” to both rows (records) and columns in a relational database. For example, Smith’s EMPLOYEE table uses an employee ID to identify each record, and its schema tables assign a column object id to each column.
  • Motivation to Combine: Petitioner contended that a person of ordinary skill in the art (POSITA) would combine the teachings of Chang and Smith. Both references are directed at improving relational database systems and are fully compatible. A POSITA would have been motivated to implement Chang’s method of using packed descriptors to improve query efficiency within a database system like Smith’s that uses explicit object identifiers for robust data management. This combination would yield the predictable benefits of both systems.
  • Expectation of Success: The combination involved applying known database principles from two similar systems, leading to a high expectation of success.

Ground 2: Obviousness over Chang, Smith, and Goldberg - Claims 6 and 36 are obvious over Chang in view of Smith and Goldberg

• Prior Art Relied Upon: Chang, Smith, and Goldberg (5,201,046).
• Core Argument for this Ground:
  • Prior Art Mapping: This ground addresses dependent claims 6 and 36, which add limitations requiring a logical row that includes information defining the type of a different logical row and a cell containing a pointer to that different row. The core combination of Chang and Smith provides the base database structure. Petitioner argued that Goldberg supplies the additional limitations by teaching a method for storing directed graph data structures within a relational database. Goldberg explicitly discloses using row-to-row pointers to link related records. For instance, a record for an "AUTOMOBILE" contains a pointer to a related record for a "POWER TRAIN," thereby defining a component relationship and type.
  • Motivation to Combine: A POSITA would combine Goldberg’s teachings with the Chang/Smith database to handle hierarchical or component-based data, a common requirement in database management. Goldberg’s pointer feature was a well-known technique for representing such relationships and was fully compatible with the relational databases described in Chang and Smith.

Ground 3: Obviousness over Chang, Smith, and Anderson - Claims 7 and 37 are obvious over Chang in view of Smith and Anderson

• Prior Art Relied Upon: Chang, Smith, and Anderson (5,463,724).

• Core Argument for this Ground:

  • Prior Art Mapping: This ground addresses dependent claims 7 and 37, which require a logical cell that includes a plurality of pointers to other logical columns within the same record. Petitioner argued that Anderson, which describes spreadsheet programs like Quattro Pro, teaches this feature. In Anderson, a cell can contain a formula with pointers (references) to multiple other cells or columns within the same row to calculate a derived value (e.g., a "SUM" formula in one cell that points to several other cells in the row).
  • Motivation to Combine: A POSITA would have been motivated to incorporate the known spreadsheet-style feature of derived columns from Anderson into the relational database of Chang/Smith. Integrating such functionality to create calculated fields was a known and desirable way to enhance database capabilities, and Anderson provided a known syntax for doing so.

• Additional Grounds: Petitioner asserted additional obviousness challenges based on Chang and Smith in further view of Webb (Oracle Distributed Systems Guide) for claims 11 and 41, and in further view of Horn (5,226,158) for claims 12-13 and 42-43. These grounds similarly relied on Webb and Horn to add teachings of specific pointer and row-typing functionalities.

4. Key Claim Construction Positions

• "Object Identification Number (OID)": The central contention driving the filing of this second petition was the meaning of OID. Petitioner noted that in parallel litigation, the Patent Owner had advocated for a narrow construction where OIDs must be "immutable and completely independent of changes in data value or physical location." Petitioner argued that while Chang's identifiers met a broader construction, the express disclosure of "object ids" for both rows and columns in Smith satisfied even the Patent Owner's newly asserted narrow construction, thereby resolving the dispute.

5. Relief Requested

• Petitioner requests institution of an inter partes review (IPR) and cancellation of claims 1-2, 6-7, 11-13, 31-32, 36-37, and 41-43 of the ’604 patent as unpatentable.