US1594003A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telephone-exchange system
Assignee: AT&T Inc
•
Filing: 1924-06-30
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Granted: 1926-07-27
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Expires: 1944-06-30
Abstract
No abstract record available.
Inventors
- 👤 Warren W Carpenter
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 15:37
CPC Classifications
H; H02; H02M; H02M3/00; H02M3/02; H02M3/04; H02M3/08; H04; H04Q; H04Q3/00; H04Q3/0004
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) | 1929-07-26 | 1930-01-25 | 1930-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1933-07-26 | 1934-01-25 | 1934-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1937-07-26 | 1938-01-25 | 1938-07-27 | $7700.00 | Window Closed / Lapsed |