In Imaginal Systematic, LLC v. Leggett & Platt, Inc., Appeal No. 2014-1845, the Federal Circuit affirmed the district court’s claim construction ruling and held that a patent’s claim language disavowed more than a single preferred embodiment from an earlier patent incorporated by reference.

In a first round of litigation, Imaginal sued L&P and Simmons for infringing three patents, including the ’402 patent, which recites a process for stapling box springs together.  In the first litigation, the district court held the asserted claims valid and infringed on summary judgment.  As a result of this lawsuit, L&P redesigned its box-spring stapling apparatus.  One design change was to use a computer system that uses an optical sensor to control the movement of both the wooden frame of the box spring and the stapling device.

Imaginal then filed a second lawsuit against L&P and Simmons, alleging that L&P’s redesigned stapling apparatus still infringed the ’402 patent.  The ’402 patent incorporates by reference an earlier patent, the ’789 patent, which explicitly requires “a vision guided stapling apparatus” that locates target sites on the wood frame and guides a stapler to these target sites.  By contrast, the ’402 patent recited a method of making box springs where one step was “moving the fastening tool without the use of a vision guidance system . . . until the fastening tool is located at a target fastening location.”  The district court construed “vision guidance system” in the ’402 patent as a “system that uses a vision or sight based method to control or direct the movement or direction of something.”  Applying this claim construction, the district court held that L&P’s redesigned product did not infringe the ’402 patent.  

On appeal, Imaginal challenged the district court’s claim construction, arguing that the ’402 patent disclaimed only the use of the vision guidance system described in the ’789 patent.  The Federal Circuit disagreed, noting that “[n]othing in the claim language purports to restrict the term ‘vision guidance system’ to one particular system.  Indeed, the claim uses the term generically, referring to ‘a’ vision guidance system—meaning one or more—rather than a specific system.”  The Federal Circuit noted that the patentee had not acted as its own lexicographer in this case, and although Imaginal could have defined “vision guidance system” to mean the vision guidance system of the ’789 patent, it did not.  The Federal Circuit further noted that the ’402 patent specification actually disclosed two different examples of vision guidance systems: that of the ’789 patent and another that provides “less exact” guidance.  The Federal Circuit reasoned that, because the ’402 patent specifically used the phrase “vision guidance system” to refer to two different systems, there was no indication that the patentee intended to disclaim only the system disclosed in the ’789 patent.