## Facts

- Inventors filed a 1971 patent application for communication cable insulation and did not respond to an office action; the application was abandoned in October 1972 and was not revived.
- In December 1972, co-workers presented a paper describing foam-skin cable insulation closely related to the inventors’ work; a later declaration asserted the paper’s subject matter originated with the inventors.
- A third-party application filed January 4, 1973 later issued as a patent that disclosed (but did not claim) the same invention and became the principal reference during examination.
- The inventors filed a later application directed to foam-skin cable insulation; it was accorded an effective filing date of March 9, 1973 under § 120.
- The later application was not co-pending with the abandoned 1971 application and did not contain a specific reference to that earlier application.
- The PTO rejected multiple claims for obviousness under 35 U.S.C. § 103 over the intervening patent reference alone or combined with another reference; the Board sustained the rejections.

## Issues

1. Whether applicants may rely on the filing date of an earlier abandoned application as a constructive reduction to practice under 35 U.S.C. § 120 when the later application was neither co-pending with nor specifically referenced the earlier application.
2. Whether, absent § 120 priority, the PTO properly treated the intervening patent as prior art and sustained § 103 obviousness rejections.

## Decision

- The Federal Circuit affirmed the Board’s decision sustaining the § 103 rejections.
- The court held the applicants could not claim the earlier abandoned application’s filing date under § 120 because the later application lacked both statutory prerequisites: copendency and a specific reference.
- Because the earlier date was unavailable, the intervening patent was properly treated as prior art in the § 103 analysis.
- Evidence suggesting the invention originated with the applicants (including a declaration regarding the symposium publication) did not substitute for § 120 compliance in this ex parte examination context.

## Legal Principles

- The benefit of an earlier filing date under 35 U.S.C. § 120 is conditioned on (1) the later application being filed before the earlier application is patented or abandoned (copendency) and (2) the later application containing a specific reference to the earlier application.
- An abandoned, unrevived application cannot supply a constructive reduction to practice date for a later application unless § 120’s conditions are satisfied.
- When § 120 priority is unavailable, an intervening patent that discloses the same subject matter may be applied as prior art for a § 103 obviousness rejection, even if the applicant asserts earlier inventive activity.

## Conclusion

The Federal Circuit required strict compliance with § 120’s copendency and specific-reference requirements; lacking those formal links, the applicants could not rely on their abandoned earlier filing date, and the PTO properly used the intervening disclosure as prior art to sustain obviousness rejections.


In re Costello, 717 F.2d 1346 (Fed. Cir. 1983)