On October 1, 2018, the Federal Circuit issued an opinion, Natural Alternatives International, Inc. v. Iancu, concerning priority claims in familial patent applications.

The Federal Circuit’s Natural Alternatives decision is an appeal of an inter partes reexamination1 of U.S. Patent No. 8,067,381 filed by Woodbolt Distributors, LLC2 in May 2012. In the inter partes reexamination, the PTAB affirmed the examiner’s rejection of all challenged claims as anticipated by, or obvious over, the prior art, including a parent of the ‘381 patent.

Priority Claims in the ‘381 Patent Family

The ‘381 patent issued from the eighth patent application in a chain of applications filed by NAI between 1997 and 2011. NAI filed the first application on August 12, 1997. Each of the second through fourth applications was a continuing application that included a priority benefit statement under 35 U.S.C. § 120 claiming priority back to the August 12, 1997, filing date of the first application.

On April 10, 2003, NAI filed a provisional application (the 2003 provisional application), and on November 18, 2003, NAI filed the fifth application as a continuation-in-part of the fourth application. The fifth application included a claim of priority to the first four applications and to the 2003 provisional application. NAI filed its sixth application during the fifth application’s pendency. At that time, the sixth application claimed priority to the fifth application, and the fifth application correctly claimed priority to the first four applications.

Four days after filing its sixth application, NAI amended the “Cross Reference of Related Applications” section of the fifth application to delete the priority claim to the first four applications and to claim priority to only the 2003 provisional application. Accordingly, when the fifth application issued, it only claimed the benefit of the filing date of the 2003 provisional application. The sixth through eighth applications included statements claiming the benefit of the filing dates of the first five applications as well as the filing date of the 2003 provisional application. However, by the time the sixth application was filed, the only pending application was the fifth application. And by the time the seventh and eight applications were filed, none of the first five applications was pending. The ‘381 patent issued from the eighth application on November 29, 2011.

The Federal Circuit’s Decision

In affirming the PTAB’s decision, the Federal Circuit determined that even though the application that issued as the ‘381 patent included a statement claiming priority to the first five applications, because the fifth application claimed priority only to the 2003 provisional application, the ‘381 patent was not entitled to a priority date any earlier than the filing date of the 2003 provisional application. In other words, the fifth application’s failure to claim priority to the four earlier applications broke the chain and precluded all subsequent applications from properly claiming priority to the first four applications.

According to the Federal Circuit, the PTAB correctly determined that “because the fifth application lacked priority to the first application, the eighth application’s priority claim to the first application (via the fifth application)” did not satisfy the “specific reference” requirement of 35 U.S.C. § 120.3 Therefore, the ‘381 patent was not entitled to claim priority to the filing date of the first application under § 120. As a consequence, the first four applications (all of which were published and/or issued as patents before the filing of the fifth application) became prior art to the ‘381 patent.

The Federal Circuit rejected NAI’s argument that “[r]ather than the dogmatic view of seeing additional continuation filings merely adding an additional link in a single growing chain, § 120, and the case law, must be interpreted as providing for a new priority chain being created at each new filing.” The Federal Circuit determined that that argument ignores “the long-standing interpretation of priority as a single chain, growing with each additional continuation. The Supreme Court has previously explained that under § 120, parent and continuing applications ‘are to be considered as parts of the same transaction, and both as constituting one continuous application, within the meaning of the law.’” Slip op. at 12 (citing Godfrey v. Eames, 68 U.S. 317, 326 (1863)).

The Federal Circuit also rejected NAI’s argument that the PTAB’s determination impermissibly “limits an applicant’s ability to seek protection” when “amending the priority claim to gain [patent] term.” In so doing, the Federal Circuit explained that:

Continuation-in-part (“CIP”) applications, like the fifth application in this case, uniquely highlight the tradeoff between priority and patent term. In CIP applications, priority is assessed on a claim-by-claim basis. … An applicant can obtain an earlier effective filing date for claims in a CIP application only if those claims find support in an earlier-filed nonprovisional application. … Claims reciting new matter, however, are entitled to only the filing date of the CIP application and not to the filing date of the earlier-filed application. … Because the standard patent term is twenty years after an application’s earliest-claimed priority date … the claims reciting new matter are not entitled to the parent application’s earlier filing date, and they therefore have a truncated patent term (i.e., less than twenty years).

In other words, if a patent applicant were to delete a priority claim in a CIP application, the 20-year patent term of the patent issuing from that CIP application would extend not from the parent application’s priority date, but from the CIP application’s filing date. However, when the CIP application utilizes its own later filing date, the CIP application (and applications claiming priority thereto) are susceptible to rejections “based on a larger pool of prior art — including former parent applications in some cases.” Slip op. at 14. NAI’s attempt to “gain patent term on its fifth application while simultaneously shielding its child applications (including the eighth application) from their former parents” was an improper attempt by NAI to have its cake and eat it too. Id.

Conclusion

The Natural Alternatives case highlights the importance of properly maintaining priority for all patent applications in a patent family. As this case shows us, not doing so can result in a finding that a patent issuing from a child application is invalid in view of earlier published family members that would not have qualified as prior art if the patent applicant had properly maintained priority.