US2881977A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Key operated portable calculating machine
Assignee: Individual
•
Filing: 1952-11-05
•
Granted: 1959-04-14
•
Expires: 1972-11-05
Abstract
No abstract record available.
Inventors
- 👤 Donald H Reeves
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 04:46
CPC Classifications
G; G06; G06C; G06C7/00; G06C7/02; G06C7/08
Claims Analysis
Total Claims: 0
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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) | 1962-04-13 | 1962-10-13 | 1963-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-04-13 | 1966-10-13 | 1967-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-04-13 | 1970-10-13 | 1971-04-14 | $7700.00 | Window Closed / Lapsed |