US1820088A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Recording apparatus
Assignee: AT&T Inc
•
Filing: 1927-09-07
•
Granted: 1931-08-25
•
Expires: 1947-09-07
Abstract
No abstract record available.
Inventors
- 👤 Ralzemond D Parker
- 👤 Fred H Best
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:21
CPC Classifications
G; G01; G01D; G01D15/00; G01D15/10; G01R; G01R13/00; G01R13/04
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) | 1934-08-24 | 1935-02-23 | 1935-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-08-24 | 1939-02-23 | 1939-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-08-24 | 1943-02-23 | 1943-08-25 | $7700.00 | Window Closed / Lapsed |