US1826338A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Perspectograph
Assignee: Individual
•
Filing: 1930-03-25
•
Granted: 1931-10-06
•
Expires: 1950-03-25
Abstract
No abstract record available.
Inventors
- 👤 Carl W Ackerberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:53
CPC Classifications
B; B43; B43L; B43L13/00; B43L13/14; B43L13/148; G; G01; G01C; G01C11/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1934-10-05 | 1935-04-06 | 1935-10-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-10-05 | 1939-04-06 | 1939-10-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-10-05 | 1943-04-06 | 1943-10-06 | $7700.00 | Window Closed / Lapsed |