## Facts

- Hilmer sought a U.S. patent on chemical subject matter, including claims 10 and 16.
- In a prior interference with Habicht (based on claim 1 of Habicht’s U.S. patent), Hilmer conceded priority of the interference count to Habicht.
- Habicht had an earlier Swiss filing date than Hilmer’s foreign filing; Habicht’s U.S. application was filed before Hilmer’s U.S. application.
- In an earlier appeal, the court held that Habicht’s U.S. patent could be used as prior art under 35 U.S.C. § 102(e) only as of Habicht’s U.S. filing date, not the Swiss priority date.
- On remand, the Board again rejected Hilmer’s claims 10 and 16 as obvious “over” the interference count (Habicht claim 1) in view of Wagner, treating Habicht as prior art via 35 U.S.C. § 102(g) based on the interference priority result.

## Issues

1. Whether subject matter corresponding to an interference count (Habicht claim 1) could be treated as patent-defeating prior art against Hilmer’s claims via 35 U.S.C. § 102(g) because Hilmer conceded priority in the interference.
2. Whether the Board could sustain an obviousness rejection by using § 102(g) to effectively give the Habicht disclosure a foreign-priority-based effective date and combine it with Wagner.

## Decision

- The court reversed the Board’s rejection of claims 10 and 16.
- The Board improperly relied on § 102(g) and the interference priority concession to treat Habicht’s subject matter as prior art with an effective date tied to Habicht’s foreign filing.
- The interference outcome did not permit the Patent Office to achieve, through § 102(g), the foreign-priority prior-art effect that was unavailable under § 102(e).

## Legal Principles

- Under pre-AIA 35 U.S.C. § 102(e), a U.S. patent is prior art only as of its U.S. filing date, not a foreign priority date.
- A priority determination or concession in an interference does not automatically make the interference count subject matter “prior art” against an applicant in ex parte prosecution under § 102(g) as of a foreign filing date.
- Section 102(g) cannot be used to circumvent statutory limits on prior-art dates by converting foreign-priority-based priority into an earlier effective prior-art date for an obviousness rejection.

## Conclusion

The court held that the Board could not use § 102(g) and an interference priority concession to treat Habicht’s interference-count subject matter as prior art as of Habicht’s foreign filing date, and it therefore reversed the obviousness rejection of Hilmer’s remaining claims.


In re Hilmer (Hilmer II), 424 F.2d 1108 (C.C.P.A. 1970)