US1472455A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Testing circuits
Assignee: AT&T Inc
•
Filing: 1919-06-24
•
Granted: 1923-10-30
•
Expires: 1939-06-24
Abstract
No abstract record available.
Inventors
- 👤 David G Blattner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 06:28
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/46
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) | 1926-10-29 | 1927-04-30 | 1927-10-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1930-10-29 | 1931-04-30 | 1931-10-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1934-10-29 | 1935-04-30 | 1935-10-30 | $7700.00 | Window Closed / Lapsed |