## Facts

- Joseph L. Hall owned an 1867 patent for an improvement in connecting safe doors and casings using conical or tapering arbors (bolts) securing multiple metal plates.
- Hall asserted infringement only of Claim 3, covering conical/tapering arbors used with two or more metal plates in safe doors and casings, secured by keys or similar means.
- The specification described arbors “tapped in” from the outside and keyed inside to bind alternating plates and resist removal.
- Hall previously obtained an 1860 patent that disclosed a cored conical bolt with a screw thread.
- Evidence showed Hall made and sold at least two safes using solid conical bolts (without screw threads) more than two years before applying for the 1867 patent, and those safes were in ordinary commercial use.
- The accused safes used conical securing elements, but the record did not establish that defendants used screw threads on the portion of any arbor located within the plates.

## Issues

1. Whether Claim 3 was invalid because the claimed subject matter was disclosed in Hall’s earlier 1860 patent and/or was in public use or on sale with Hall’s consent more than two years before the 1867 application.
2. Whether defendants infringed Claim 3 under a construction requiring arbors with screw threads (i.e., “tapped into” the plates) on the portion within the plates.

## Decision

- The Supreme Court affirmed dismissal of Hall’s infringement suit.
- If Claim 3 required threaded arbors “tapped into” the plates, defendants were not proven to infringe because their arbors were not shown to have screw threads within the plates.
- If Claim 3 covered unthreaded, solid conical arbors, the claim was invalid because the subject matter was disclosed in Hall’s earlier patent and had been in public use and on sale more than two years before the 1867 application.

## Legal Principles

- A patent claim is invalid if the claimed invention was in public use or on sale in the United States, with the inventor’s consent, more than two years before the application under the then-governing patent statutes.
- An inventor’s own earlier patent disclosure can anticipate and defeat novelty of a later claim covering the same invention.
- Adding a screw thread to an already-known solid conical bolt, without a materially different result, is not a patentable invention.
- A patentee cannot prevail where, under one reasonable claim construction, infringement is not proven, and under the alternative construction necessary to reach the accused device, the claim is invalid.

## Conclusion

The Court held Hall could not recover on Claim 3 because construing it to require threaded arbors defeated infringement on the proof, while construing it broadly enough to cover unthreaded conical bolts rendered the claim invalid based on Hall’s earlier patent disclosure and Hall’s own commercial sales and public use more than two years before the application.


Hall v. Macneale, 107 U.S. 90 (1883)