US2976367A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Two-stage line concentrator system
Assignee: AT&T Inc
•
Filing: 1958-12-23
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Granted: 1961-03-21
•
Expires: 1978-12-23
Abstract
No abstract record available.
Inventors
- 👤 Bruce Edmond
- 👤 Willard A Reenstra
- 👤 Wesson J Ritchie
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 02:46
CPC Classifications
H; H04; H04Q; H04Q3/00; H04Q3/0008; H04Q3/0012; H04Q3/42; H04Q3/52; H04Q3/525
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2333324A
Cited
US2820103A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-03-20 | 1964-09-19 | 1965-03-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-03-20 | 1968-09-19 | 1969-03-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-03-20 | 1972-09-19 | 1973-03-21 | $7700.00 | Window Closed / Lapsed |