Patent US1607673A successfully refreshed from Google Patents.
US1607673A
Expired / Lapsed
US
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Telephone-substation circuits
Assignee: AT&T Inc
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Filing: 1924-10-09
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Granted: 1926-11-23
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Expires: 1944-10-09
Abstract
No abstract record available.
Inventors
- 👤 Alfred H Inglis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:02
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/60; H04M1/6033
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) | 1929-11-22 | 1930-05-24 | 1930-11-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1933-11-22 | 1934-05-24 | 1934-11-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1937-11-22 | 1938-05-24 | 1938-11-23 | $7700.00 | Window Closed / Lapsed |