## Facts

- Competing manufacturers in the textile industry produced open-end spinning (OES) equipment.
- Two related patents covering OES improvements were owned by Hans and Fritz Stahlecker and exclusively licensed to Spindelfabrik Suessen-Schurr Stahlecker & Grill GmbH: U.S. Patent Nos. 4,059,946 and 4,175,370.
- Suessen alleged Schubert’s OES machine, the “Spincomat,” infringed claim 18 of the ’946 patent and multiple claims of the ’370 patent.
- Separately, Murata Machinery owned U.S. Patent No. 4,022,011 and licensed it to Schubert; Schubert relied on that license when producing and marketing the Spincomat.
- While Suessen’s infringement suit was pending, Suessen acquired Murata’s ’011 patent and acknowledged Schubert’s existing license to the ’011 patent.
- The district court held the ’946 and ’370 patents valid and infringed; rejected defenses including implied license; found willful infringement of the ’946 patent; and awarded enhanced damages and attorney’s fees.
- After judgment, Schubert introduced a redesigned Spincomat; the district court found the redesign still infringed the ’946 patent and granted injunctive relief.
- Schubert appealed the infringement-related rulings, including the implied-license/estoppel defense, the redesign finding, and the enhanced damages and fee award.

## Issues

1. Whether Schubert’s license under Murata’s ’011 patent, coupled with Suessen’s later acquisition of the ’011 patent, created an implied license or legal estoppel barring Suessen from enforcing the separate ’946 patent.
2. Whether the district court correctly found the original Spincomat infringed the asserted claims of the ’946 and ’370 patents.
3. Whether the district court correctly found Schubert’s redesigned Spincomat still infringed the ’946 patent and could be enjoined.
4. Whether the findings supporting enhanced damages for willful infringement and an attorney-fee award under 35 U.S.C. § 285 were proper.

## Decision

- The Federal Circuit affirmed the district court on all appealed infringement-related questions.
- The court rejected Schubert’s implied-license/legal-estoppel theory based on Suessen’s acquisition of Murata’s ’011 patent.
- The court upheld the findings that the original Spincomat infringed the asserted claims of the ’946 and ’370 patents.
- The court upheld the finding that the redesigned Spincomat infringed the ’946 patent and affirmed injunctive relief against it.
- The court affirmed enhanced damages for willful infringement and the attorney-fee award under § 285 (as awarded for conduct attributable to infringement of the ’946 patent).

## Legal Principles

- A license under one patent does not, without more, confer a license under a different patent, even if the patents concern related technology or later come under common ownership.
- Legal estoppel supporting an implied license must rest on the conduct or grant of rights by the patentee whose patent is being asserted; a third party’s license does not, by itself, bar enforcement of a separate patent held by a different entity.
- A post-judgment redesign that retains claim-required features may still infringe and may be subject to injunction.
- Findings of willful infringement can support enhanced damages, and “exceptional case” findings can support attorney’s fees under 35 U.S.C. § 285 when the record supports the district court’s determinations.

## Conclusion

The Federal Circuit affirmed findings of infringement of two OES patents and affirmed enhanced damages, attorney’s fees, and injunctive relief, holding that Schubert’s license to a different, later-acquired patent did not create an implied license or estop enforcement of Suessen’s separate patent rights.


Spindelfabrik Suessen-Schurr Stahlecker & Grill GmbH v. Schubert & Salzer Maschinenfabrik Aktiengesellschaft, 829 F.2d 1075 (Fed. Cir. 1987)