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US1646387A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic telephone system
Assignee: Siemens and Halske AG
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Filing: 1925-08-21
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Granted: 1927-10-25
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Expires: 1945-08-21
Abstract
No abstract record available.
Inventors
- 👤 Preuss Alexander Bruno
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 23:03
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/0016
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) | 1930-10-24 | 1931-04-25 | 1931-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1934-10-24 | 1935-04-25 | 1935-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1938-10-24 | 1939-04-25 | 1939-10-25 | $7700.00 | Window Closed / Lapsed |