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US3372381A
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Digital computer teaching machine
Assignee: AT&T Inc
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Filing: 1965-01-06
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Granted: 1968-03-05
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Expires: 1985-01-06
Abstract
No abstract record available.
Inventors
- 👤 Raspanti Matthew
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 18:09
CPC Classifications
G; G09; G09B; G09B19/00; G09B19/0053; G06; G06F; G06F11/00; G06F11/30; G06F11/32; G06F11/324; G06F11/325; G06F3/00; G06F3/14; G06F3/147; G06F11/323
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-03-05 | 1971-09-04 | 1972-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-03-05 | 1975-09-04 | 1976-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-03-05 | 1979-09-04 | 1980-03-05 | $7700.00 | Window Closed / Lapsed |