## Facts

- A PTO interference concerned a catalytic process for producing alkylidene diesters used in manufacturing vinyl acetate and acetic acid.
- Paulik and Schultz (employees of Monsanto) achieved actual reduction to practice in November 1970 and again in April 1971.
- Around November 20, 1970, Paulik submitted an internal invention disclosure to Monsanto’s patent department; it was assigned a lower internal priority and was not promptly filed.
- After years of delay, Monsanto’s patent solicitor began preparing an application in early 1975, requested additional experiments, and worked on drafts.
- Paulik’s patent application was filed June 30, 1975.
- Rizkalla and Winnick (associated with Halcon SD Group) had an effective filing date of March 10, 1975 through a parent application.
- The Board of Patent Interferences awarded priority to Rizkalla, finding Paulik’s multi-year delay after reduction to practice amounted to “suppression or concealment” under 35 U.S.C. § 102(g).
- The Board treated the delay as dispositive and declined to consider Paulik’s evidence of renewed patent-related activity begun before Rizkalla’s effective filing date.

## Issues

1. Whether a lengthy period of inactivity after reduction to practice constitutes “suppression or concealment” under 35 U.S.C. § 102(g) as an automatic forfeiture of priority.
2. Whether a first inventor may rebut an inference of suppression or concealment by showing renewed efforts to patent or otherwise advance the invention that begin before the second inventor enters the field.
3. Whether the Board committed legal error by refusing to consider evidence of such renewed activity when deciding priority.

## Decision

- The Federal Circuit vacated the Board’s priority award and remanded.
- The court held that a long period of inactivity does not necessarily produce a fatal, irrevocable loss of priority under § 102(g).
- The court held that renewed activity by the first inventor, if begun before the second inventor’s entry, can rebut an inference of suppression or concealment and must be considered.
- The court rejected the Board’s view that an early reduction to practice categorically barred reliance on later pre-filing activity to negate suppression or concealment.

## Legal Principles

- Under pre-AIA 35 U.S.C. § 102(g), priority generally favors the first actual inventor unless that inventor abandoned, suppressed, or concealed the invention.
- A substantial delay between reduction to practice and public disclosure or filing may support an inference of suppression or concealment, but the inference is rebuttable.
- Suppression or concealment is not established by delay alone; the factfinder must evaluate the inventor’s overall course of conduct, including indications of continued interest and steps toward disclosure.
- Evidence of renewed efforts to prepare and file a patent application, when initiated before the rival inventor’s entry, is probative on whether earlier inactivity amounted to suppression or concealment and must be weighed.

## Conclusion

The Federal Circuit required the Board to evaluate whether the first inventor’s later, pre-entry efforts to pursue patenting rebutted any inference that earlier delay constituted suppression or concealment, and remanded for a priority determination under that standard.


Paulik v. Rizkalla, 760 F.2d 1270 (Fed. Cir. 1985)