According to statute, if prosecution of a patent application is delayed due to the fault of the United States Patent and Trademark Office (“USPTO”), additional term is added to the life of the patent when it issues. This is called patent term adjustment. In the case of In re Cellect, Fed. Cir. Aug 28, 2023, we learn of patents that were gifted this additional term, but as a result the patents were invalid.

These patents were continuations-in-part in a family of related patents. Families of related patents are generated to more thoroughly cover an inventive achievement with claims of varying scope and wording. Some patents in the family claimed roughly the same invention but in different ways. This raised the spectre of obviousness-type double patenting (“ODP”). ODP as explained by the Federal Circuit depends on “whether the claims of a later expiring patent would have been obvious over the claims of an earlier expiring patent owned by the same party. If so, absent a terminal disclaimer, the later expiring claims are invalid.” A terminal disclaimer shortens the term of a patent so that it does not remain active beyond the life of the patent having claims that are patentably indistinguishable.

Given that the patent applications of the family were contemporaneously being prosecuted with claims that were close enough to be patentably indistinguishable, the patent examiner could have issued a provisional obviousness-type double patenting rejection on the claims. In order to overcome such a rejection, the patent applicant would need to demonstrate that the claims were actually nonobvious from those of the other patent or otherwise file a terminal disclaimer. Since the same examiner was responsible for examining all of the relevant patents in the family, the examiner had before him or her the information necessary to issue such a provisional obviousness-type double patenting rejection. But no such rejection was issued.

When the patents were issued, some of them were granted patent term adjustment so that their available term was longer than that of some of the other patents in the family. While the extra patent term is normally a welcome development, it left those patents vulnerable to an obviousness-type double patenting challenge. The USPTO failed to forestall such a challenge by its failure to issue a provisional obviousness-type double patenting rejection that would have alerted the patentee to the need for a terminal disclaimer. The USPTO allowed a challenger to go forward with an ex parte re-examination on obviousness-type double patenting grounds, essentially admitting its failure to previously consider this issue. The Federal Circuit Court of Appeals agreed that obviousness-type double patenting was a substantial new question that had not been considered by the examiner during prosecution. Thus, four ex parte re-examinations were allowed to go forward against four of the patents in the family that had longer patent terms due to patent term adjustments. Without patentably distinguishable claims or terminal disclaimers to give back the added patent term, the patents were held invalid.

Practice Tips

• Do what you can to make the examiner aware of the co-pending or prior patent applications in a family. This is typically done by filing an information disclosure statement listing of earlier related patents or co-pending patent applications. For the co-pending patent applications, copies of the applications and perhaps copies of office actions may need to be provided.
• A terminal disclaimer may be filed even after a patent has issued as long as the patent is still in force. So review your issued patents that belong to a family of patents for the possibility of obviousness-type double patenting where one patent expires later than another patent with patentably indistinguishable claims, and file terminal disclaimers as needed.

Recommendations for the USPTO

The possibility of obviousness type double patenting provides one more uncertainty as to the enforceability of a patent. The USPTO could help deliver more certainty to the patent system by requiring its examiners to consider the question of obviousness-type double patenting with respect to patents and patent applications coming from the same family. If the examiners affirmatively note that this issue has been considered, the USPTO could readily turn away post-issuance challenges on the basis of a lack of substantial new question of patentability. At least as far as the USPTO is concerned, the issue will have been resolved during the initial patent examination and therefore not new and open to re-examination at a later date. Such a practice would provide an additional ounce of certainty to the system.