Patent US2630853A successfully refreshed from Google Patents.
Patent US2401994A successfully refreshed from Google Patents.
Patent US2821948A successfully refreshed from Google Patents.
US2821948A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Water craft having hydroplanes
Assignee: Individual
•
Filing: 1956-02-06
•
Granted: 1958-02-04
•
Expires: 1976-02-06
Abstract
No abstract record available.
Inventors
- 👤 Ulysses S Harkson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 03:31
CPC Classifications
B; B63; B63B; B63B1/00; B63B1/16; B63B1/18; B63B1/20; B63B2001/183
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2704529A
Cited
US1749017A
Cited
US1835618A
Cited
GB485572A
Cited
US2400782A
Cited
US2564597A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-02-03 | 1961-08-05 | 1962-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-02-03 | 1965-08-05 | 1966-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-02-03 | 1969-08-05 | 1970-02-04 | $7700.00 | Window Closed / Lapsed |