US1856774A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Loud speaker construction
Assignee: Ambac International Corp
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Filing: 1930-11-15
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Granted: 1932-05-03
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Expires: 1950-11-15
Abstract
No abstract record available.
Inventors
- 👤 Carl A Mayer
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:44
CPC Classifications
H; H04; H04R; H04R9/00; H04R9/02; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49005; Y10T29/4957
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1935-05-03 | 1935-11-02 | 1936-05-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1939-05-03 | 1939-11-02 | 1940-05-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1943-05-03 | 1943-11-02 | 1944-05-03 | $7700.00 | Window Closed / Lapsed |