US2981940A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Communication systems
Assignee: International Business Machines Corp
•
Filing: 1957-03-11
•
Granted: 1961-04-25
•
Expires: 1977-03-11
Abstract
No abstract record available.
Inventors
- 👤 Richard L Garwin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 20:39
CPC Classifications
H; H02; H02J; H02J13/00; H02J13/13; H02J13/1311; H02J13/1313; Y; Y02; Y02E; Y02E60/00; Y04; Y04S; Y04S40/00; Y04S40/12; Y04S40/121
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2337441A
Cited
US2574458A
Cited
US2619547A
Cited
US2581056A
Cited
US2636164A
Cited
US2842753A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-04-24 | 1964-10-24 | 1965-04-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-04-24 | 1968-10-24 | 1969-04-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-04-24 | 1972-10-24 | 1973-04-25 | $7700.00 | Window Closed / Lapsed |