US2521540A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Prefabricated panel and warming means therefor
Assignee: Individual
•
Filing: 1946-09-17
•
Granted: 1950-09-05
•
Expires: 1966-09-17
Abstract
No abstract record available.
Inventors
- 👤 Max C Richardson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 13:12
CPC Classifications
F; F24; F24D; F24D13/00; F24D13/02; F24D13/022; E; E04; E04C; E04C2/00; E04C2/44; E04C2/52; E04C2/521; Y; Y02; Y02B; Y02B30/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US395950A
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US574745A
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US761204A
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US1368412A
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US1476116A
Cited
GB225627A
Cited
GB224648A
Cited
US1703640A
Cited
GB427255A
Cited
GB447453A
Cited
US2328666A
Cited
US2393100A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-09-04 | 1954-03-06 | 1954-09-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-09-04 | 1958-03-06 | 1958-09-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-09-04 | 1962-03-06 | 1962-09-05 | $7700.00 | Window Closed / Lapsed |