US3457526A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Notch filter
Assignee: AT&T Inc
•
Filing: 1965-05-11
•
Granted: 1969-07-22
•
Expires: 1985-05-11
Abstract
No abstract record available.
Inventors
- 👤 William H Orr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 10:01
CPC Classifications
H; H03; H03B; H03B5/00; H03B5/20; H03H; H03H11/00; H03H11/02; H03H11/04; H03H11/12; H03H11/1295; H03B2201/00; H03B2201/01
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2549553A
Cited
US2619534A
Cited
US3072868A
Cited
US2996689A
Cited
US3009121A
Cited
US3174111A
Cited
US3223941A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-07-21 | 1973-01-20 | 1973-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-07-21 | 1977-01-20 | 1977-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-07-21 | 1981-01-20 | 1981-07-22 | $7700.00 | Window Closed / Lapsed |