US2496639A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Aid for the blind
Assignee: AT&T Inc
•
Filing: 1946-04-26
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Granted: 1950-02-07
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Expires: 1966-04-26
Abstract
No abstract record available.
Inventors
- 👤 Jr John W Richardt
- 👤 Oscar A Shann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 14:08
CPC Classifications
A; A61; A61H; A61H3/00; A61H3/06; A61H3/061; A61H3/068; G; G01; G01S; G01S15/00; G01S15/02; G01S15/06; G01S15/42; G01S15/88; G01S15/93; A61H2003/063; Y; Y10; Y10S; Y10S367/00; Y10S367/91
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) | 1953-02-06 | 1953-08-08 | 1954-02-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-02-06 | 1957-08-08 | 1958-02-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-02-06 | 1961-08-08 | 1962-02-07 | $7700.00 | Window Closed / Lapsed |