US2573889A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Automatic telephone switching mechanism
Assignee: Individual
•
Filing: 1948-12-14
•
Granted: 1951-11-06
•
Expires: 1968-12-14
Abstract
No abstract record available.
Inventors
- 👤 Hans P Boswau
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:45
CPC Classifications
H; H01; H01H; H01H67/00; H01H67/22; H01H67/26
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-11-05 | 1955-05-07 | 1955-11-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-11-05 | 1959-05-07 | 1959-11-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-11-05 | 1963-05-07 | 1963-11-06 | $7700.00 | Window Closed / Lapsed |