In Boehringer Ingelheim Int’l v. Barr Labs and Mylan Pharma (Fed. Cir. 2010), the Federal Circuit made an interesting statement regarding the judicially created doctrine of obviousness-type double patenting — that the doctrine has been historically important.
The doctrine of obviousness-type double patenting is an important check on improper extension of patent rights through the use of divisional and continuation applications, at least for patents issued from applications filed prior to the amendment of 35 U.S.C. § 154 to create twenty-year terms running from the date of the earliest related application.
As suggested, the advent of a twenty-year term based on application priority date means that the justification for a double patenting rejection is largely becoming a moot-point. And, I suspect that the court will eventually change the law by holding that a terminal disclaimer is not necessary if the two patent terms are already identical. A family of patents filed in the past decade will typically all have roughly the same ending-dates except for differences created by patent term extensions and adjustments (PTE & PTA). In my view, applicants should be allowed to take advantage of those extensions apart from any terminal disclaimer. The other hang-up with terminal disclaimers is that they require the two applications be commonly owned.