US3535797A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Teaching machine film
Assignee: Individual
•
Filing: 1968-07-17
•
Granted: 1970-10-27
•
Expires: 1988-07-17
Abstract
No abstract record available.
Inventors
- 👤 John C L Leslie
- 👤 Burton E Dieruf
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:25
CPC Classifications
G; G09; G09B; G09B7/00; G09B7/06; G09B7/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-10-26 | 1974-04-27 | 1974-10-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-10-26 | 1978-04-27 | 1978-10-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-10-26 | 1982-04-27 | 1982-10-27 | $7700.00 | Window Closed / Lapsed |