During the pendency of a patent application, the US Patent and Trademark Office can restrict claims, requiring that the Applicant elect a sub combination or a species and select claims directed to the sub combination or species.  The Applicant has the option of electing and selecting while traversing the restriction, or electing and selecting without traversal.  What are the risks and benefits of each of these paths?

A divisional patent application can be filed, in order to pursue claims directed to an unelected sub combination or species, whether or not the restriction requirement is traversed.  Also, claims are subject to rejoinder.  If a claim that links two or more sub combinations or species is allowed, withdrawn dependent claims directed to an unelected sub combination or species, if addressed by the linking claim, can be rejoined.  Some clients prefer a patent family (e.g., a parent application and one or more divisional applications, possibly also a continuation application, etc.) to a single patent, in a portfolio.  The patent family may have better survivability to legal challenges later on, and greater value.

Traversing the restriction involves asserting that the restriction itself is improper, and indicating that the restriction should be withdrawn so that all of the claims (or a specified subset) can be pursued in a single patent application.  So, traversing the restriction, if successful, reduces costs for the Applicant as compared to prosecuting the present patent application and filing and prosecuting one or more divisional patent applications.  Particularly, maintenance costs for a patent family are greater than for a single patent.

There is a potential downside, however, to traversing the restriction.  One strategy is declaring, essentially, that all of the claims are directed to a single invention (and are thus not properly subject to a restriction requirement).  The caution here is that the application becomes subject to prosecution history estoppel.  If the restriction requirement is withdrawn and the Examiner finds a reference that claims directed to one of the earlier-asserted sub combinations or species read on, the Examiner can issue a rejection based on 35 USC §102 or 35 USC §103.  Since the Applicant has essentially declared (in the prosecution history) that all of the claims are directed to a single invention, it may be more difficult to argue novelty or nonobviousness, or amend the claims to distinguish from the reference.  On the other hand, if the restriction is not traversed, it may be easier to argue that the claims directed to the elected sub combination or species, or an aspect thereof, are distinct from what is shown in a cited reference, as the Examiner has already stated the claimed sub combinations or species are distinct, and Applicant has agreed.

Another strategy is applicable if the Examiner declares that species claimed by the Applicant are mutually exclusive, and the Examiner requires a restriction.  The Applicant can traverse the restriction by arguing that the species are not mutually exclusive, and provide a showing from the specification as to such, without putting on the record that the claims are directed to a single invention.  This allows for flexibility during prosecution of the patent application.

To sum up, traversing a restriction requirement may save costs but risk rejection.  The restriction requirement may be insisted upon by the USPTO, i.e., the Applicant may lose the argument regarding traversal, but the Applicant statements are nonetheless on record in the prosecution history and might be applied later to the detriment of the claims.  Electing and selecting without traversal may increase total costs, but the Applicant leaves less on record, and can pursue one or more divisional patent applications, thus retaining options.