Patent US2801855A successfully refreshed from Google Patents.
US2801855A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Mathematics game apparatus
Assignee: Individual
•
Filing: 1953-09-17
•
Granted: 1957-08-06
•
Expires: 1973-09-17
Abstract
No abstract record available.
Inventors
- 👤 Elmer D Clay
- 👤 Agnes D Clay
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:58
CPC Classifications
A; A63; A63F; A63F3/00; A63F3/04; A63F3/0457; G; G09; G09B; G09B19/00; G09B19/02
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US543722A
Cited
US777268A
Cited
US830424A
Cited
US1073786A
Cited
US1415019A
Cited
US1402807A
Cited
US1532722A
Cited
US1730418A
Cited
GB296599A
Cited
US1723377A
Cited
US2355785A
Cited
US2565702A
Cited
US2562633A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-08-05 | 1961-02-04 | 1961-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-08-05 | 1965-02-04 | 1965-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-08-05 | 1969-02-04 | 1969-08-06 | $7700.00 | Window Closed / Lapsed |