## Facts

- Mary Hallock Greenewalt owned a reissue patent (Reissue No. 16,825) claiming a method and means for associating light and music.
- The asserted method claims (claims 8–17) covered producing music while simultaneously varying light color and intensity in timed relationship to the emotional or aesthetic content of the music (claim 10 treated as representative).
- Greenewalt had given public performances as early as 1914 (including at Perkiomen Seminary and in Dayton, Ohio) that practiced the claimed method before audiences paying admission.
- Stanley Company of America, a theatre operator, was accused of infringing the method claims by using a system combining light and music in motion-picture exhibitions.
- The district court dismissed the infringement suit, finding the claims barred by public use more than two years before the relevant patent application under Rev. Stat. § 4886.
- Greenewalt appealed.

## Issues

1. Whether Greenewalt’s paid public performances in 1914 constituted a public use more than two years before the patent application, barring the claims under Rev. Stat. § 4886.
2. Whether claims directed to coordinating light color and intensity with the emotional or aesthetic content of music state patent-eligible subject matter as a statutory “art” or “process,” or instead claim an unpatentable aesthetic performance concept.

## Decision

- The Third Circuit affirmed dismissal of the complaint.
- The court held the method claims invalid on two independent grounds:
  - The claims were barred by prior public use more than two years before the patent application.
  - The claims were not within statutory patent subject matter because they sought protection for an intangible aesthetic experience dependent on performer choice and audience reaction.
- The court rejected reliance on an asserted experimental purpose because the prior uses were commercial public exhibitions.

## Legal Principles

- Paid public performances that practice an invention can constitute “public use” and trigger the statutory bar when they are commercial transactions rather than testing directed to perfecting the invention.
- An inventor’s undisclosed intent to experiment does not avoid the public-use bar where the objective facts show public, commercial exploitation.
- A claimed “process” is not patentable when it effectively claims a method of artistic or aesthetic expression whose operation and results depend on human artistry, caprice, and subjective audience response rather than a definite, repeatable technological result.

## Conclusion

The court upheld dismissal because the patented method of synchronizing light effects with music was both commercially used in public more than two years before the application and, in any event, claimed nonstatutory subject matter by attempting to monopolize an intangible aesthetic performance experience.


Greenewalt v. Stanley Co. of Am., 54 F.2d 195 (3d Cir. 1931)