Patent US2547804A successfully refreshed from Google Patents.
US2547804A
Expired / Lapsed
US
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Telephone line identification system
Assignee: Automatic Telephone and Electric Co Ltd
•
Filing: 1947-06-13
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Granted: 1951-04-03
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Expires: 1967-06-13
Abstract
No abstract record available.
Inventors
- 👤 Baker George Thomas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:51
CPC Classifications
H; H04; H04M; H04M15/00; H04M15/08
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) | 1954-04-02 | 1954-10-02 | 1955-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-04-02 | 1958-10-02 | 1959-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-04-02 | 1962-10-02 | 1963-04-03 | $7700.00 | Window Closed / Lapsed |