"Virtual Client Entity" Deemed Indefinite By District Court Under MPF Analysis

The District Court for the District of Delaware recently handed down a claim construction order in T-JAT Systems 2006 v. Expedia that held the claim limitation "virtual client entity" was indefinite under 35 U.S.C. § 112, ¶2. The court concluded that the claim limitation was indefinite after determining that "virtual client entity" should be interpreted as invoking 35 U.S.C. § 112, ¶6 (means-plus-function) and then ascertaining that the specification failed to provide sufficient structure for "virtual client entity."

Claim 1, which was deemed representative, recited:

A method for providing a user of a telephone device with a capability to use Internet-based applications, which method comprises the steps of:

transmitting from said telephone device an indication towards a first server, denoting a request to be connected to an Internet-based application residing at a second server;

providing said user with a menu from which the user selects a requested Internetbased application;

after selecting an application, establishing a communication path that extends between said telephone device and said second server via said first server;

at said first server, creating a virtual client entity specific to said telephone device and said Internet-based application to be used, created specifically to allow communication between said telephone device and said Internet-based application residing at said second server, and maintained only for the duration of a communication session that is about to take place between said user and said Internet-based application, thereby providing the user of said telephone device with the capability to use said Internet-based application; and

exchanging communications between said second server and said telephone device.

The Defendant argued, and the court agreed, that "virtual client entity" was governed by 35 U.S.C. § 112, ¶6. The Patent Owner proposed construing the limitation as "an instance of executable software that emulates connectivity and/or resources of a computing device or software adapted to connect and request information from a server."

However, using the framework set forth under Williamson v. Citrix Online, LLC, 792 F.3d 1339 (Fed. Cir. 2015), the court determined that "virtual client entity" invoked means-plus-function analysis under 35 U.S.C. § 112, ¶6. Noting that the limitation did not include the term "means," the court concluded that the claim limitation recited the "function of allowing communication between the telephone device and Internet-based application." Thus, the key question in the court's eyes was whether the term "virtual client entity" provided sufficient structure to perform that function.

The court disagreed with the Patent Owner's arguments that a person of ordinary skill in the art would have understood that the claim limitation connoted sufficient structure at the time of filing. Instead, the court relied on the Patent Owner's definition and found that the only structural element associated with the definition was the term "program," as in a software program. The court then went on to find that the program was purely defined by the functionality.

As set forth in Williamson, "the fact that one of skill in the art could program a computer to perform the recited functions cannot create structure where none is otherwise disclosed." With computer programs, the specification must disclose sufficient structure, such as in the form of an algorithm, for performing the claimed function, and the court found that the Patent Owner failed to identify any algorithms within the specification related to the functionality of the "virtual client entity."

Patent Prosecution Tips

This case provides the continued lesson that patent practioners should include one or more flow diagrams for claim limitations that could be interpreted as invoking means-plus-function. Flow diagrams and the corresponding descriptions within the specification can equate to algorithms.

Additionally, patent practioners may want to include additional claim language that provides sufficient structure. For example, consider " a virtual client entity that is configured to receive data from an input, generate an answer based on the data, and transmit the answer via an output." One can argue that these terms define specific structure within the claims and are not merely functional language.