US3403623A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for marking symbols and other subject matter on charts, graphs and the like
Assignee: WILLIAM R BLACKWOOD
•
Filing: 1967-03-01
•
Granted: 1968-10-01
•
Expires: 1987-03-01
Abstract
No abstract record available.
Inventors
- 👤 William R Blackwood
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 21:03
CPC Classifications
B; B41; B41K; B41K1/00; B41K1/36; B41K1/02
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
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) | 1971-10-01 | 1972-04-01 | 1972-10-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-10-01 | 1976-04-01 | 1976-10-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-10-01 | 1980-04-01 | 1980-10-01 | $7700.00 | Window Closed / Lapsed |