## Facts

- Applicants sought patent claims (6–10) to a chemical process for preparing a specific cephem antibiotic compound by introducing a particular acyl group into a cephem amino group (an acylation reaction).
- The process was limited to using an organic acid side chain containing a 2-aminothiazolyl group and producing a specific cephem product with antibiotic properties.
- The examiner rejected the process claims as obvious under 35 U.S.C. § 103 based on six references describing acylation chemistry in the relevant field.
- The Board of Patent Appeals and Interferences affirmed the § 103 rejection.
- The starting organic acid and the resulting cephem product were each treated as new and nonobvious as of the invention date (and were the subject of separate patents).
- On appeal, the claims were treated as standing or falling together because applicants did not separately argue them before the Board.

## Issues

1. Whether the PTO may sustain a § 103 rejection of a process claim by effectively applying a categorical rule that a conventional reaction type renders the process obvious, despite the claim being limited to using and producing nonobvious chemical compounds.
2. Whether, under § 103, the prior art must provide a reason to carry out the conventional process steps with the specific nonobvious reactants and toward the specific nonobvious product recited in the claim.

## Decision

- The Federal Circuit reversed the Board’s decision and the examiner’s § 103 rejection.
- The court held the Board’s analysis was legally erroneous because it rested on an impermissible per se approach to obviousness for process claims.
- Applying a fact-specific obviousness inquiry, the court found the cited references did not suggest using the particular 2-aminothiazolyl acyl side chain with the claimed cephem nucleus to achieve the claimed process and product.

## Legal Principles

- Obviousness under 35 U.S.C. § 103 requires a claim-by-claim, fact-dependent analysis; categorical or per se rules are improper.
- A process claim must be evaluated “as a whole,” and limitations that define the process by making or using a nonobvious product are material and must be given weight.
- For a § 103 rejection of such a process claim, the prior art must supply a reason to make or use the specific nonobvious product (and thus to select the specific reactants and target recited), not merely disclose similar reaction types.
- The conventionality of the reaction mechanism (e.g., acylation) does not alone establish obviousness when the claim is confined to particular nonobvious chemical materials and results.

## Conclusion

The Federal Circuit held that process claims limited to making or using nonobvious chemical products cannot be rejected as obvious based on a generalized view that conventional reaction steps make the process obvious; the PTO must instead show, from the prior art, a reason to perform those steps with the specific nonobvious reactants and toward the specific nonobvious result recited in the claim.


In re Ochiai, 71 F.3d 1565 (Fed. Cir. 1995)