US1624422A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dial-testing circuit
Assignee: AT&T Inc
•
Filing: 1926-06-30
•
Granted: 1927-04-12
•
Expires: 1946-06-30
Abstract
No abstract record available.
Inventors
- 👤 Robert B Miller
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 02:54
CPC Classifications
H; H04; H04Q; H04Q3/00
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1930-04-11 | 1930-10-11 | 1931-04-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1934-04-11 | 1934-10-11 | 1935-04-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1938-04-11 | 1938-10-11 | 1939-04-12 | $7700.00 | Window Closed / Lapsed |