Reissue and Reexamination Applications in the Correction of Patents

Up until now, we have discussed patent applications that are used to obtain patent claims for an invention. Reissue applications and reexamination applications are used in a different way. They are two of a number of procedures that may be used to address defects in patents after they have issued.

In order to file a reissue application, the patent owner must include a declaration identifying an error that was made in the application that renders the resulting patent “wholly or partially inoperable.” This may include errors in inventorship, claiming priority, misstatements in the specification, or errors in the description of experiments. The important point is that there must be an identified error. A reissue cannot be used simply to improve a patent because it has been poorly drafted or prosecuted, and no new matter can be added.

Importantly, the USPTO recognizes that claims that are too broad or too narrow in scope relative to what is actually supported are considered correctable errors. As a result, reissue is often the best—and sometimes the only—method for changing the scope of issued claims. This can become important, for example, if a patent does not adequately cover a commercially important embodiment or if newly discovered prior art requires the claims to be narrowed to preserve validity.

There are, however, limits on how reissue can be used. Claims may only be broadened during the first two years after the patent issues, while claims may be narrowed at any time during the life of the patent. For this reason, patent owners must consider relatively early whether the scope of the claims is appropriate.

Reexamination serves a different, but related, role. It is typically used when there is a question as to whether the issued claims are valid in light of prior art that was not fully considered during the original examination. In that sense, reexamination focuses less on correcting errors in wording or scope, and more on reassessing the patentability of the claims based on additional information.

Unlike reissue, reexamination does not require the patent owner to admit that an error was made. It may also be requested by a third party seeking to challenge the validity of the claims. While that use of reexamination raises its own set of strategic considerations, it also means that reexamination can play a role in confirming or strengthening a patent when potential issues are identified.

A reexamination begins with a request identifying prior art and explaining why it raises a question of patentability. If the Patent Office agrees that the issue is significant, the patent is reconsidered through a further examination process. The outcome may be that the claims are confirmed, narrowed, or, in some cases, cancelled.

A procedure closely related to reexamination is supplemental examination. The principal differences are that it may only be requested by the patent owner, that a broader range of information may be submitted, and that the cost is significantly higher. Its principal advantage is that it can, under appropriate circumstances, address issues that might otherwise raise concerns about inequitable conduct.

Other mechanisms also exist for addressing issues in issued patents, and in some cases the need for correction can be reduced by maintaining a continuation application in prosecution. Nevertheless, reissue and reexamination have unique features that often make them the most appropriate tools when defects in an issued patent must be addressed.

Disclaimer: This piece is provided for general informational purposes only and does not constitute legal advice. Patent issues are often complex and highly fact-specific, and no one should act on general information of this kind without consulting qualified patent counsel regarding the particular circumstances involved.