Patent US2809571A successfully refreshed from Google Patents.
US2809571A
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US
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Identification camera
Assignee: Individual
•
Filing: 1953-03-17
•
Granted: 1957-10-15
•
Expires: 1973-03-17
Abstract
No abstract record available.
Inventors
- 👤 Christensen William
- 👤 Robert M Lanspeary
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:33
CPC Classifications
G; G03; G03B; G03B17/00; G03B17/24; G03B17/245; G03B2217/00; G03B2217/24; G03B2217/241; G03B2217/242; G03B2217/243
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US619309A
Cited
US1150543A
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US1208617A
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US1205085A
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US1645590A
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US1693876A
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US2347749A
Cited
US2345999A
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US2541016A
Cited
US2475898A
Cited
US2529896A
Cited
US2632369A
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 |