US2521558A
Expired / Lapsed
US
⏱️ 0.0 years remaining
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Assignee: ALVAREZ PATENT Corp
•
Filing: 1946-02-20
•
Granted: 1950-09-05
•
Expires: 1966-02-20
Abstract
No abstract record available.
Inventors
- 👤 Alvarez Octavio Jose
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:13
CPC Classifications
G; G02; G02B; G02B27/00; G02B27/02; G02B27/022; G02B27/024; G02B27/025; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49826; Y10T29/49863; Y10T29/49876
Claims Analysis
Total Claims: 0
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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 |