## Facts

- W.L. Gore & Associates, Inc. owned patents covering a high-rate stretching process for polytetrafluoroethylene (PTFE) and porous PTFE products made by that process (U.S. Patent Nos. 3,953,566 and 4,187,390).
- Dr. Robert Gore discovered in 1969 that rapidly stretching highly crystalline PTFE “as fast as possible” could produce very high elongation without breakage and with significant changes in material properties.
- Gore filed the patent application on May 21, 1970; the ’566 patent claimed the stretching process, and the ’390 patent claimed products produced by that process.
- Garlock, Inc. was accused of infringement and counterclaimed for declaratory judgments of invalidity and noninfringement.
- Garlock relied heavily on alleged earlier activity involving a PTFE stretching machine developed by Cropper and used by Budd Company.
- Cropper had offered the machine for sale to a third party, but no sale or further disclosure occurred.
- Budd used the Cropper machine under confidentiality restrictions, including a confidential agreement with Cropper and secrecy obligations imposed on Budd employees.
- After a bench trial, the district court held both patents invalid for anticipation (§ 102), obviousness (§ 103), and indefiniteness (§ 112), including a finding that “rate of stretch” was indefinite.
- Gore appealed; Garlock cross-appealed. The Federal Circuit reviewed the invalidity rulings and the need for further proceedings on infringement.

## Issues

1. Whether a third party’s secret, confidential commercial use of an invention constitutes prior art (or “public use”/“known or used by others”) that can anticipate or render obvious a later-filed patent under 35 U.S.C. §§ 102 and 103.
2. Whether an unconsummated offer to sell, without enabling disclosure of the invention, can qualify as invalidating prior art under § 102.
3. Whether the claim term “rate of stretch,” read in light of the specification, is indefinite under 35 U.S.C. § 112.
4. What disposition is required when substantial portions of an invalidity judgment are set aside and infringement was not determined.

## Decision

- The Federal Circuit affirmed in part, reversed in part, and remanded.
- The court reversed invalidity determinations to the extent they treated Budd’s confidential use of Cropper’s machine as anticipating or rendering the inventions obvious.
- The court held that secret, non-public use by a third party, kept under confidentiality, is not prior art for purposes of §§ 102 and 103.
- The court rejected reliance on Cropper’s unconsummated offer to sell where there was no enabling disclosure or public availability of the invention’s details.
- The court reversed the indefiniteness ruling in relevant part, concluding that “rate of stretch” was not fatally indefinite when construed in context of the specification and the knowledge of skilled artisans.
- The case was remanded for determination of infringement in light of the corrected validity analysis.

## Legal Principles

- Prior art under § 102, and predicates for obviousness under § 103, require public accessibility; third-party secret commercialization or confidential use does not constitute “public use” or “known or used by others” for invalidity.
- An isolated offer to sell that does not result in sale or enabling public disclosure does not, by itself, place the invention in the public domain for § 102 purposes.
- Definiteness under § 112 is assessed by reading the claims in view of the specification and the understanding of a person skilled in the art; absolute precision is not required if the claim boundary can be determined with reasonable certainty.
- Evidence that the prior art taught away from the claimed approach, together with unexpected results, may support nonobviousness.

## Conclusion

The Federal Circuit held that confidential third-party use and a non-enabling, unconsummated sales offer could not be used as prior art to invalidate Gore’s PTFE stretching patents, and it rejected the district court’s indefiniteness ruling as to “rate of stretch,” remanding for a determination of infringement under the corrected legal standards.


W.L. Gore & Assocs., Inc. v. Garlock, Inc., 721 F.2d 1540 (Fed. Cir. 1983)