In the precedential case In re: Cellect, LLC, Docket Nos. 2022-1293, 1294, 1295, and 1296 (Fed. Cir., Aug. 28, 2023), the Federal Circuit affirmed the PTAB’s invalidation of four expired Cellect patents during ex parte reexamination.  Even though the four patents were expired, they were still within a back damages period, and Cellect had sued Samsung for infringement of the four patents.

 

It is a common US patent practice to, through continuation applications, base multiple issued patents on a same priority application.  Ordinarily, all such patents would expire on the same date, twenty years from filing of the priority application.  Cellect had been granted a family of 12 patents in this case, all tied to the same priority application.

 

When extended USPTO delays eat up a portion of a patent’s 20-year term, 35 U.S.C. § 154(b) triggers a Patent Term Adjustment (PTA) to be added to the end of the patent’s life.  Some of Cellect’s patents were granted promptly by the USPTO, and some others were delayed (up to two years) due to delays in the USPTO.

 

Because two years of damages were at stake, Samsung complained that the later-expiring patents should not have extended beyond the earlier expiration of sister patents with similar claims, which had not been held up at the USPTO.  This judge-made doctrine, “obviousness-type double patenting” or ODP, is regularly seen during patent prosecution where two patents in a family have claims of overlapping scope.  It is normally overcome by the applicant filing a terminal disclaimer, which among other things, is an agreement that the two patents shall expire on the earliest expiration date of the two.  Section 154(b) specifically negates added PTA in the case of a terminal disclaimer.

 

The patents at issue here were not terminally disclaimed, although the Examiner was aware of the sister patents’ existence.  Accordingly, when the PTAB found that the Examiner should have applied ODP and required a terminal disclaimer but there was no evidence the issue was considered, Cellect was stuck.  Because the patents are already expired, it was too late to terminally disclaim them, and so the only remedy was invalidity.  The Federal Circuit agreed.

 

For patentees with important patent families (or patents on closely related technology that aren’t part of the same family), this case may be significant.  One important takeaway from this case is that just because an Examiner did not assert ODP during prosecution, that does not mean that a later-issued patent is not at risk from a co-owned earlier-issued patent claiming similar concepts.  Because the later-issued patent often has claims that are better stated (and thus more valuable) due to the knowledge gained during earlier prosecution, this type of collateral attack should be considered before assertion, and possibly a terminal disclaimer should be filed in close cases.  In strategic prosecution, a possible preemptive strategy could involve placing the issue of ODP squarely before the Examiner, and arguing why it should not apply.