Patent US3010087A successfully refreshed from Google Patents.
US3010087A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Equalizer
Assignee: AT&T Inc
•
Filing: 1958-11-14
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Granted: 1961-11-21
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Expires: 1978-11-14
Abstract
No abstract record available.
Inventors
- 👤 Grace L Ebbe
- 👤 Robert V Sperry
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 07:22
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/04; H04B3/14; H04B3/146; H04B3/148
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1371471A
Cited
US2002192A
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US2107025A
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US2529117A
Cited
US2542160A
Cited
US2589184A
Cited
US2816179A
Cited
US2848564A
Cited
US2922128A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-11-20 | 1965-05-22 | 1965-11-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-11-20 | 1969-05-22 | 1969-11-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-11-20 | 1973-05-22 | 1973-11-21 | $7700.00 | Window Closed / Lapsed |