Conflicting Interpretations Invalidate Patent for Indefiniteness: Infinity Computer Prods., Inc. v. Oki Data Americas, Inc.

What is a computer, when recited in a patent claim? The Federal Circuit recently discussed whether a recitation of a “computer” in a claim was indefinite under 35 U.S.C. § 112 in light of conflicting interpretations by the patentee. Infinity Computer Prods., Inc. v. Oki Data Americas, Inc. 2020-1189 (Fed. Cir. Feb. 10, 2021).

Plaintiff Infinity asserted several patents against Defendant Oki Data, including U.S. Patent No. 6,894,811. The asserted patents are directed to communications between a fax machine and a computer. Claim 1 of the ‘811 patent is representative, and recites, in part:

A method of creating a scanning capability from a facsimile machine to a computer, with scanned image digital data signals transmitted through a bi-directional connection via a passive link between the facsimile machine and the computer, comprising the steps of:

conditioning the facsimile machine to transmit digital signals representing data on a scanned document to the computer, said computer being equipped with send/receive driver communications software enabling the reception of scanned image signals from the facsimile machine, said transmitted digital facsimile signals being received directly into the computer through the bi-directional direct connection via the passive link, thereafter, said computer processing the received digital facsimile signals of the scanned document as needed.

The district court considered whether the phrase “a passive link between the facsimile machine and the computer” was indefinite under 35 U.S.C. § 112. A patent is invalid for indefiniteness under § 112 if “if its claims, read in light of the specification delineating the patent, and the prosecution history, fail to inform, with reasonable certainty, those skilled in the art about the scope of the invention.” Nautilus, Inc. v. Biosig Instruments, Inc., 572 U.S. 898 (2014). During claim construction, the district court held that the recitation “a passive link between the facsimile and the computer” is indefinite under § 112 and invalidated the ‘811 patent because it was not clear where the “facsimile machine” ended and the “computer” began.

The Court affirmed the district court’s ruling, noting that the Plaintiff took different interpretations of the “passive link” and the “computer” during prosecution of the ‘811 patent. First, following an Office Action, Plaintiff introduced the “passive link” language to overcome prior art. The term “passive link” does not appear in the ‘811 patent, but Plaintiff argued that with the “passive link,” the fax machine could provide data directly to the I/O bus of the “computer,” bypassing other “peripheral devices,” such as a fax modem. That is, the “computer” in this first interpretation does not include the fax modem.

Then, during an ex parte reexamination, to overcome other prior art, Plaintiff introduced an expert declaration to define “passive link.” During this proceeding, Plaintiff argued that the cable connecting the fax machine to the computer was the “passive link,” ending at the hardware port of the “computer.” In this interpretation, the “computer” includes the fax modem. The Court held that, because Plaintiff had separately argued that the term “passive link” defined the “computer” to both include the fax modem and not include the fax modem, there “is no reasonable certainty” “where the passive link ends and the computer begins.”

Lessons for Practice

When using terms that may not have a plain, ordinary meaning, take care that the interpretation that you want for the terms is expressed clearly in the patent and the prosecution history. Following Nautilus, courts have greater discretion to invalidate patents for indefiniteness, so providing context and even explicit definitions for those terms can help avoid problems down the line.