US3500559A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electronic system for accepting and processing responses to questions presented to students
Assignee: General Electric Co
•
Filing: 1967-09-11
•
Granted: 1970-03-17
•
Expires: 1987-09-11
Abstract
No abstract record available.
Inventors
- 👤 Leonidas J Jones
- 👤 Richard W Rankin
- 👤 Everett L Rivest
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:24
CPC Classifications
G; G09; G09B; G09B7/00; G09B7/06; G09B7/07; G09B7/077
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3303472A
Cited
US3186110A
Cited
US3270438A
Cited
US3300876A
Cited
US3266174A
Cited
US3344408A
Cited
US3399469A
Cited
US3314172A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-03-16 | 1973-09-15 | 1974-03-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-03-16 | 1977-09-15 | 1978-03-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-03-16 | 1981-09-15 | 1982-03-17 | $7700.00 | Window Closed / Lapsed |