US2436384A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sound recording device
Assignee: AT&T Inc
•
Filing: 1941-12-19
•
Granted: 1948-02-24
•
Expires: 1961-12-19
Abstract
No abstract record available.
Inventors
- 👤 Fletcher Harvey
- 👤 John F Muller
- 👤 Jr Karl D Swartzel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 01:41
CPC Classifications
F; F42; F42C; F42C13/00; F42C13/06; Y; Y10; Y10T; Y10T137/00; Y10T137/0971; Y10T137/108; Y10T137/1098; Y10T137/1135
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) | 1951-02-23 | 1951-08-25 | 1952-02-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-02-23 | 1955-08-25 | 1956-02-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-02-23 | 1959-08-25 | 1960-02-24 | $7700.00 | Window Closed / Lapsed |