## Facts

- Susan M. Maxwell obtained U.S. Patent No. 4,624,060 for a retail system that attaches mated pairs of shoes using tabs and a filament so pairs stay together without damaging the shoes.
- The asserted claims required, among other elements, a fastening tab “secured between” the shoe’s inner and outer soles and forming a loop for a connecting filament.
- J. Baker, Inc. used multiple shoe-pairing systems supplied by manufacturers, including an “under the sock lining” version.
- After receiving patent notice (June 1, 1990), J. Baker implemented redesigned systems: a “counter pocket” version (tab stitched into the counter pocket) and a “top line” version (tab stitched into the top line seam).
- Maxwell sued in the District of Minnesota for infringement of claims 1–3.
- A jury found the patent valid, found infringement, found post-notice willfulness, found marking compliance under 35 U.S.C. § 287(a), and awarded damages largely using a per-pair reasonable royalty applied to a large sales base.
- The district court denied JMOL/new trial motions, enhanced post-notice damages, awarded prejudgment interest, and entered a permanent injunction.
- J. Baker appealed, contesting infringement (especially of the redesigns), damages, marking, and validity (prior inventorship).

## Issues

1. Whether J. Baker’s “under the sock lining,” “counter pocket,” and “top line” systems infringed claims 1–3, literally or under the doctrine of equivalents.
2. Whether embodiments disclosed in the patent specification but not claimed could be reached through the doctrine of equivalents, or instead were dedicated to the public.
3. Whether the damages award was legally supportable where it included sales tied to noninfringing systems.
4. Whether Maxwell satisfied the marking requirement of 35 U.S.C. § 287(a) through reasonable efforts to ensure licensee marking.
5. Whether substantial evidence supported rejection of J. Baker’s prior-inventorship challenge to validity.

## Decision

- The Federal Circuit affirmed in part, reversed in part, vacated in part, and remanded.
- It affirmed infringement as to the “under the sock lining” system (at least under the doctrine of equivalents).
- It reversed infringement findings for the “counter pocket” and “top line” systems, holding they did not infringe even under the doctrine of equivalents because those approaches were disclosed but unclaimed and thus dedicated to the public.
- It vacated the damages award to the extent it was based on sales using the noninfringing “counter pocket” and “top line” systems and remanded for recalculation limited to infringing sales.
- It affirmed the finding that Maxwell satisfied § 287(a) marking based on continuous reasonable efforts to secure licensee compliance.
- It affirmed validity, concluding substantial evidence supported rejection of the prior-inventorship defense.

## Legal Principles

- Subject matter disclosed in a patent specification but not claimed is dedicated to the public and cannot be recaptured via the doctrine of equivalents.
- The doctrine of equivalents cannot be used to extend coverage to disclosed alternative embodiments that the patentee chose not to claim, because doing so would impair the notice function of claims and bypass examination of unclaimed scope.
- Patent damages must be tied to actual infringement; a reasonable royalty base must exclude sales of products found noninfringing, requiring apportionment where multiple designs are accused.
- For § 287(a), a patentee who licenses the patented article must make reasonable efforts to ensure licensees mark; perfect, continuous compliance is not required if reasonable efforts are shown.
- On appellate review of a jury verdict, validity challenges such as prior inventorship fail where substantial evidence supports the jury’s findings.

## Conclusion

The Federal Circuit sustained infringement only for J. Baker’s “under the sock lining” system, rejected liability for redesigns that matched disclosed-but-unclaimed embodiments, and required damages to be recalculated to exclude noninfringing sales, while affirming marking compliance and validity.


Maxwell v. J. Baker, Inc., 86 F.3d 1098 (Fed. Cir. 1996)