US3393764A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Loudspeaker systems
Assignee: Individual
•
Filing: 1966-12-27
•
Granted: 1968-07-23
•
Expires: 1986-12-27
Abstract
No abstract record available.
Inventors
- 👤 Curtiss R Schafer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 00:39
CPC Classifications
H; H04; H04R; H04R1/00; H04R1/20; H04R1/22; H04R1/227; H04B; H04B1/00; H04B1/06; H04B1/16; H04B1/22
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
DE1075666B
Cited
US2114680A
Cited
US2544742A
Cited
DE975222C
Cited
US2768702A
Cited
FR1196858A
Cited
US3054856A
Cited
US3074503A
Cited
US3136382A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-07-23 | 1972-01-22 | 1972-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-07-23 | 1976-01-22 | 1976-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-07-23 | 1980-01-22 | 1980-07-23 | $7700.00 | Window Closed / Lapsed |