## Facts

- Lyle B. Borst filed a patent application (Serial No. 654,837) on April 24, 1957, titled “Neutron Amplifier.”
- The claimed invention used a controllable neutron source to produce a larger neutron output through a subcritical reaction, aiming for safe control of neutron multiplication.
- Illustrative claim 27 recited a “subcritical neutron amplifier” with: (1) a controllable neutron source; (2) an input moderator region converting epithermal neutrons to thermal levels; (3) a sequent subcritical fuel region configured to augment neutron flow by fission; and (4) an output thermal-neutron barrier substantially opaque to thermal neutrons but transmissive to epithermal neutrons.
- Related claims (27–33) included variations such as adjusting barrier transparency, time-based modulation of neutron flow, and placing the fuel in a hydrogenous environment.
- The Patent Office rejected claims 27–33 as unpatentable, relying primarily on a 1947 Samsel memorandum that had been classified and not publicly available until about 1957.
- The Patent Office Board of Appeals affirmed the examiner’s rejection.
- Borst appealed to the United States Court of Customs and Patent Appeals.

## Issues

1. Whether a classified, nonpublic government memorandum could qualify as prior art for purposes of rejecting patent claims under the novelty provisions.
2. Whether the Samsel memorandum anticipated claims 27–33 by disclosing every claim element arranged as required, with sufficient teaching to support the rejection.
3. Whether the claimed neutron amplifier would have been obvious in view of Samsel and other art or general knowledge, if Samsel did not strictly anticipate.

## Decision

- The court reversed the Board of Appeals’ decision and set aside the rejection of claims 27–33.
- The court concluded the Samsel memorandum did not provide an adequate basis to sustain anticipation of the claimed configuration, including the moderator/fuel/barrier arrangement.
- The court was not persuaded that the record supported denying patentability based on Samsel alone or in combination with other art.

## Legal Principles

- Anticipation requires a single reference to disclose each element of the claimed invention, arranged as in the claim, with disclosure sufficient to permit a person skilled in the art to practice the invention.
- A document treated as prior art must fall within statutory prior-art categories; secrecy and restricted circulation weigh against treating internal, classified materials as prior art because they are not publicly accessible.
- For complex subject matter, patentability must be assessed based on the claimed combination and arrangement, not by isolating individual features that may be known in the field.
- An obviousness rejection requires a supported showing that the prior art would have led a skilled artisan to the claimed arrangement with a sufficient reason to combine and an expectation of success.

## Conclusion

The C.C.P.A. reversed the Patent Office’s rejection of Borst’s neutron amplifier claims, holding that the classified Samsel memorandum did not justify anticipation (and did not support rejection when considered with other materials), and emphasizing that nonpublic, restricted disclosures generally cannot function as prior art against a patent applicant.


Application of Borst, 345 F.2d 851 (C.C.P.A. 1965)