US2676213A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Telephone listening aid
Assignee: Individual
•
Filing: 1951-08-20
•
Granted: 1954-04-20
•
Expires: 1971-08-20
Abstract
No abstract record available.
Inventors
- 👤 John F Anderson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 05:43
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/02; H04M1/04; H04M1/05
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-04-19 | 1957-10-19 | 1958-04-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-04-19 | 1961-10-19 | 1962-04-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-04-19 | 1965-10-19 | 1966-04-20 | $7700.00 | Window Closed / Lapsed |