In Uship Intellectual Properties, LLC v. US, the US Court of Appeals for the Federal Circuit issued a May 8, 2013 opinion affirming the Court of Federal Claims' (CFC) ruling on summary judgment that the US Postal Service and IBM do not infringe Uship's patents directed to automatic systems and methods for preparing packages for shipment. The claims at issue recite a method of mailing parcels and envelopes using an automated shipping machine in the preamble. They comprise several similar or identical steps, including receiving payment information from a customer, receiving package type information identifying a parcel to be mailed, printing a shipping label and validating receipt of the parcel.

The key issue on appeal was whether the claimed "validating" step can be carried out only by an automated shipping machine, or, as Uship argued, also by a human being. The Federal Circuit affirmed the CFC's claim construction limiting the "validating" step to performance by a machine, finding that the patent applicant's response to a restriction requirement resulted in prosecution history disclaimer.

During prosecution of the parent application of the patents-in-suit, the examiner asserted that the pending method and apparatus claims covered two distinct inventions and required the applicant to restrict the invention to either group of claims. In response, the applicant argued that the restriction was improper because the claims "specifically recite in the preamble a method of mailing parcels. . . 'using an automated shipping machine' rather than specifically reciting at each step that the step is performed by the automated shipping machine."

In rejecting Uship's argument that a response to a restriction requirement can never result in prosecution history disclaimer, the Federal Circuit noted that its precedents broadly state that an applicant's statements to the USPTO characterizing its invention may give rise to a prosecution disclaimer. It therefore held that a patent applicant's response to a restriction requirement may be used to interpret patent claim terms or as a source of disclaimer. The court further clarified that even if the specification disclosed an embodiment where a human performed the validation step, as Uship alleged, prosecution disclaimer could result in that embodiment not being covered by the claims.

Notably, although ruling in the US's and IBM's favor, the Federal Circuit also rejected their separate argument that the appearance of the phrase "using an automated shipping machine" in the preamble raises a presumption that every step of the claimed method must be performed by a machine, finding no support in its precedents for this presumption.