Patent US1925909A successfully refreshed from Google Patents.
US1925909A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telegraph exchange system
Assignee: Siemens and Halske AG
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Filing: 1932-04-13
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Granted: 1933-09-05
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Expires: 1952-04-13
Abstract
No abstract record available.
Inventors
- 👤 Rossberg Ehrhard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 11:54
CPC Classifications
H; H04; H04L; H04L12/00; H04L12/02; H04L12/14; H04L12/1432; H04L12/1439
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) | 1936-09-04 | 1937-03-06 | 1937-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1940-09-04 | 1941-03-06 | 1941-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1944-09-04 | 1945-03-06 | 1945-09-05 | $7700.00 | Window Closed / Lapsed |