Consider a typical situation where an inventor files a patent application, the application is examined and allowed, and the inventor elects to file a continuation application to seek additional patent claim coverage. If everything proceeds without delay, the continuation patent and the original patent would expire on the same day based on the original application filing date.

But what if the USPTO creates unjust delay when examining the continuation application? One would think the inventor would be compensated for the delay, particularly as the patent statute requires such a patent term adjustment.

The USPTO, as the Federal Circuit recently affirmed, has said not so fast. The continuation application may be invalidated when it claims an obvious-variant of the original patent claims under the non-statutory doctrine of obviousness double patenting. The USPTO would require the applicant to excuse the USPTO’s unjust delay by filing a disclaimer of the term corresponding to the statutory patent term adjustment.

In crowded art spaces where USPTO delay is common, this ruling could drastically effect patent practice concerning continuation applications. If a continuation application takes longer to prosecute than the original patent, the continuation may be left with little to no term. A successful ex parte appeal of a continuation application claiming an obvious variant would likely be subject to a term reduction. In an extreme case, what would prevent the USPTO from unilaterally electing not to prosecute continuation applications claiming obvious variants? There would be no statutory recourse to recover patent term caused by such delay, and the non-statutory doctrine of obviousness double patent would trump the statutory guarantee of patent term.