## Facts

- Space Systems/Loral, Inc. (SSL) owned U.S. Patent No. 4,537,375 covering a “prebias” method for satellite attitude control and station keeping that uses stored data from prior maneuvers to correct for thruster imbalances before a primary maneuver.
- Dr. Fred Chan, working for SSL’s predecessor, conceived the method but continued engineering and testing for months; as of early 1982, he was uncertain the approach would work as proposed.
- In March 1982, SSL’s predecessor sent a proposal to Aérospatiale describing the prebias approach with rough drawings and cost estimates, but without a tested engineering implementation or complete enabling technical detail.
- SSL filed the patent application on April 21, 1983.
- Lockheed Martin was sued for infringement and moved for summary judgment that the patent was invalid under 35 U.S.C. § 102(b) based on the March 1982 proposal.
- The district court granted summary judgment, treating the proposal as an offer for sale made more than one year before filing and finding the invention “ready for patenting.”
- SSL appealed.

## Issues

1. Whether the March 1982 proposal triggered the § 102(b) on-sale bar under the two-part test of *Pfaff v. Wells Electronics, Inc.* by constituting a commercial offer for sale and involving an invention “ready for patenting” more than one year before the filing date.
2. Whether disputed facts concerning the proposal’s character and the development status of the invention precluded summary judgment of invalidity.

## Decision

- The Federal Circuit reversed the summary judgment of invalidity and remanded.
- The court held that the district court misapplied the § 102(b) on-sale bar by not properly applying *Pfaff*’s “ready for patenting” requirement and by treating the proposal as dispositive despite factual disputes.
- The court concluded that genuine issues of material fact existed as to whether the invention was ready for patenting in March 1982 and whether the proposal was a commercial offer to sell the claimed invention.

## Legal Principles

- Under *Pfaff*, the § 102(b) on-sale bar requires (1) a commercial offer for sale and (2) that the invention was “ready for patenting” at the time of the offer.
- “Ready for patenting” may be shown by reduction to practice or by drawings/descriptions sufficiently specific to enable a person skilled in the art to practice the claimed invention.
- Whether a pre-filing proposal concerns the invention “as claimed” requires comparison of the proposal’s content to the claim limitations.
- On-sale bar invalidity is a question of law with underlying factual determinations; summary judgment is improper where material facts are disputed regarding the nature of the offer or readiness for patenting.

## Conclusion

The Federal Circuit held that a pre-filing proposal does not establish an on-sale bar as a matter of law where the record supports disputes about whether the proposal was a commercial offer of the claimed invention and whether the invention was ready for patenting under *Pfaff*, requiring reversal of summary judgment and remand for further proceedings.


Space Sys./Loral, Inc. v. Lockheed Martin Corp., 271 F.3d 1076 (Fed. Cir. 2001)