## Facts

- Two research teams separately sought U.S. patent rights to an HPV virus-like particle (VLP) vaccine technology.
- Ian Frazer and Jian Zhou (Frazer) pursued a U.S. application claiming priority to an Australian filing (July 19, 1991) and a later PCT filing; their work described VLPs that mimic HPV capsids but lack viral DNA.
- Frazer’s early experimental disclosure described VLP formation using HPV-16 L1 and L2 proteins; later work reflected that L1 alone could form VLPs.
- C. Richard Schlegel and A. Bennett Jenson (Schlegel) filed a U.S. application on June 25, 1992 for similar HPV VLP vaccine technology.
- The PTO declared an interference to determine priority under pre-AIA law.
- The Board of Patent Appeals and Interferences ruled Frazer could not rely on the 1991 Australian filing because it allegedly failed U.S. disclosure requirements; the Board awarded priority to Schlegel based on Schlegel’s U.S. filing date.
- Frazer appealed, arguing the Australian application adequately described the invention and supported the earlier priority date.

## Issues

1. Whether Frazer’s Australian application satisfied the U.S. written description requirement for the interfering subject matter, entitling Frazer to the July 19, 1991 priority date.
2. Whether the Board erred by treating alleged scientific inaccuracies or later technical refinements as defeating written description and priority in an interference.

## Decision

- The Federal Circuit reversed the Board’s priority award to Schlegel.
- The court held Frazer was entitled to the Australian application’s July 19, 1991 filing date.
- With that earlier effective filing date, Frazer prevailed on priority in the interference.

## Legal Principles

- A party may rely on a foreign priority application in a U.S. interference only if that application satisfies U.S. disclosure requirements for the claimed invention, including written description.
- Written description asks whether the application shows the inventors were in possession of the invention as of the filing date, not whether every scientific characterization is later confirmed or optimally described.
- Scientific dispute, later refinement, or improved understanding does not necessarily negate written description where the original disclosure conveys the core invention to a person skilled in the art.
- If an earlier priority application adequately supports the interfering subject matter, its filing date controls priority over a later U.S. filing.

## Conclusion

The Federal Circuit concluded that Frazer’s Australian filing adequately described the HPV VLP vaccine invention under U.S. written description standards, so Frazer received the 1991 priority date and won priority over Schlegel in the PTO interference.


Frazer v. Schlegel, 498 F.3d 1283 (Fed. Cir. 2007)