Patent US3501592A successfully refreshed from Google Patents.
US3501592A
Expired / Lapsed
US
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Telephone answering apparatus with cueing and warning signals
Assignee: Electrospace Corp
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Filing: 1964-03-30
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Granted: 1970-03-17
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Expires: 1984-03-30
Abstract
No abstract record available.
Inventors
- 👤 Herbert Waldman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:04
CPC Classifications
H; H04; H04M; H04M1/00; H04M1/64; H04M1/65; H04M1/6515
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2799726A
Cited
US2793252A
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US2848541A
Cited
US2815401A
Cited
US2928893A
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US3310629A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-03-16 | 1973-09-15 | 1974-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-03-16 | 1977-09-15 | 1978-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-03-16 | 1981-09-15 | 1982-03-17 | $7700.00 | Window Closed / Lapsed |