US2457892A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pulse testing equipment
Assignee: AT&T Inc
•
Filing: 1943-06-26
•
Granted: 1949-01-04
•
Expires: 1963-06-26
Abstract
No abstract record available.
Inventors
- 👤 Frank H Hibbard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 00:12
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/24
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) | 1952-01-04 | 1952-07-05 | 1953-01-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-01-04 | 1956-07-05 | 1957-01-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-01-04 | 1960-07-05 | 1961-01-04 | $7700.00 | Window Closed / Lapsed |