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US272866A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Speaking-trumpet for receiving-telephones
Assignee: —
•
Filing: —
•
Granted: 1883-02-27
•
Expires: 1900-02-27
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 07:40
CPC Classifications
H; H04; H04R; H04R1/00; H04R1/20; H04R1/22; H04R1/30
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) | 1886-02-26 | 1886-08-28 | 1887-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1890-02-26 | 1890-08-28 | 1891-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1894-02-26 | 1894-08-28 | 1895-02-27 | $7700.00 | Window Closed / Lapsed |