US2990811A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Marking chalk sharpener
Assignee: Individual
•
Filing: 1960-05-31
•
Granted: 1961-07-04
•
Expires: 1980-05-31
Abstract
No abstract record available.
Inventors
- 👤 Mackie William
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:42
CPC Classifications
B; B43; B43L; B43L23/00; Y; Y10; Y10T; Y10T83/00; Y10T83/222; Y10T83/869; Y10T83/8773; Y10T83/8798; Y10T83/8812; Y10T83/8815
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1292181A
Cited
US2185985A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1964-07-03 | 1965-01-02 | 1965-07-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1968-07-03 | 1969-01-02 | 1969-07-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1972-07-03 | 1973-01-02 | 1973-07-04 | $7700.00 | Window Closed / Lapsed |