Differences between a provisional patent application and a nonprovisional application claiming priority to the provisional application may inform claim construction, following the Federal Circuit’s recent decision in MPHJ Tech v. Ricoh.[1] In MPHJ Tech, the Federal Circuit affirmed an inter partes review decision in which the Patent and Trademark Appeal Board (PTAB) found claims of a patent held by MPHJ invalid on grounds of anticipation and obviousness.[2] The patent at issue, U.S. Patent No. 8,488,173, describes a “virtual copier” that replicates an image into other devices, applications or the internet with the press of a “Go” button.[3]

On appeal, MPHJ argued that the PTAB erred in adopting an overly broad construction of the claims, leading to a finding of anticipation and obviousness. Specifically, MPHJ asserted that the claims should be more narrowly construed as requiring a one-step operation without human intervention, effectively distinguishing the claims from the prior art.[4] MPHJ drew support for the narrower construction from statements in its provisional application that allegedly “expressly limited the scope of the invention to a one-step copying and sending process.”[5] However, the identified statements in the provisional application were omitted from the nonprovisional application.

The court agreed that “a provisional application can contribute to understanding of the claims.”[6] Despite acknowledging that the statements in the provisional application were not explicitly disclaimed, the court proceeded to reason that it was the “deletion from the ’798 Provisional application that contributes understanding of the intended scope of the final application.”[7] The court highlighted excerpts of the issued patent that mention “an optional single-step operation,” which the court described as “in accord” with the change from the provisional application to the final application. Concluding that a person skilled in the field would reasonably conclude that the inventor intended the single-step operation to be optional and not obligatory, the court affirmed the PTAB’s construction.

As is often the case with patent law jurisprudence, the decision in MPHJ Tech yields more questions than it provides answers. For example, is the MPHJ Tech decision limited to changes in a specification or does it apply to changes in claims? Festo Corp. established a presumptive bar to the doctrine of equivalents in the context of infringement analysis based on narrowing of claims. However, post-MPHJ Tech, if a provisional application contains claims, a narrowing of the claims in the nonprovisional application may impact claim scope through the doctrine of prosecution history estoppel (as applied to the doctrine of equivalents) or ordinary claim construction.

Further, in light of MPHJ Tech, do changes in a specification bear on analysis under the doctrine of equivalents?[8] For example, may changes in a specification be taken to convey an intended scope of the function, way or result of a claimed element? More generally, does the MPHJ Tech decision extend to claim construction in the infringement context, where the Phillips standard of claim construction instead of the broadest reasonable interpretation standard is applied?[9]

Nevertheless, the MPHJ Tech decision does provide a few takeaways. In converting a provisional application to a nonprovisional application, changes to the content of the application should be made with the utmost care and deliberation. Changes should be purposeful, and their possible effect on claim construction should be considered. In fact, when making changes to a provisional application, it may be prudent to operate under the assumption that all changes will later be scrutinized to determine the intended scope of the invention.

The MPHJ Tech decision reminds us that the value of a well-drafted provisional application cannot be overstated. Prevention is often the best medicine in patent law, and an airtight provisional application may save a patent holder from needless legal predicaments during prosecution and beyond.