## Facts

- Invitrogen owned U.S. Patent No. 4,981,797, claiming a process to produce transformable *E. coli* cells of improved competence.
- Claim 1 required, in order: (a) growing *E. coli* at 18°C to 32°C, (b) rendering cells competent, and (c) freezing the cells.
- Stratagene made 34 competent *E. coli* cell lines using a process that included fermenter growth at 26°C and freezing.
- More than one year before filing, Invitrogen used the claimed process internally in its laboratories for research and development.
- Invitrogen maintained confidentiality and did not sell the process or any products made by the process before the critical date.

## Issues

1. Whether an inventor’s confidential, internal use of a claimed process more than one year before filing constitutes a “public use” under 35 U.S.C. § 102(b).
2. Whether Stratagene’s process infringed the ’797 patent.
3. Whether the ’797 patent was invalid for indefiniteness under 35 U.S.C. § 112.

## Decision

- Reversed the district court’s summary judgment that the ’797 patent was invalid under the § 102(b) public-use bar and remanded for reconsideration under the correct standard.
- Affirmed summary judgment that Stratagene infringed the asserted claims.
- Affirmed the determination that the ’797 patent was not invalid for indefiniteness.

## Legal Principles

- “Public use” under 35 U.S.C. § 102(b) focuses on public accessibility or commercial exploitation without limitation, restriction, or secrecy obligations.
- Confidential, internal use is not automatically “public use” merely because it confers a commercial benefit; the inquiry depends on all circumstances, including secrecy measures and control of access.
- On infringement, a process practicing the claimed ordered steps, including a growth temperature within the claimed range, can satisfy the claim limitations under the governing claim construction.
- A patent is not indefinite where claim terms and ordered steps, read in view of the specification and the understanding of a person of ordinary skill, provide reasonably clear boundaries.

## Conclusion

The Federal Circuit held that the district court applied an incorrect legal standard by treating Invitrogen’s confidential internal use as a per se public use under § 102(b), reversed the resulting invalidity judgment, and remanded, while affirming infringement and rejecting indefiniteness.


Invitrogen Corp. v. Biocrest Mfg., L.P., 424 F.3d 1374 (Fed. Cir. 2005)