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US2809452A
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US
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Assignee: Individual
•
Filing: 1953-02-11
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Granted: 1957-10-15
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Expires: 1973-02-11
Abstract
No abstract record available.
Inventors
- 👤 Meyer M Brown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 21:30
CPC Classifications
G; G02; G02B; G02B25/00; G02B25/002
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US555876A
Cited
GB190426689A
Cited
US822841A
Cited
US990918A
Cited
GB173849A
Cited
US1554905A
Cited
US1903104A
Cited
GB467854A
Cited
US2692530A
Cited
US2601619A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-10-14 | 1961-04-15 | 1961-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-10-14 | 1965-04-15 | 1965-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-10-14 | 1969-04-15 | 1969-10-15 | $7700.00 | Window Closed / Lapsed |