Patent US3023668A successfully refreshed from Google Patents.
US3023668A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Portable slide projector
Assignee: Pharmacia and Upjohn Co
•
Filing: 1957-02-21
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Granted: 1962-03-06
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Expires: 1977-02-21
Abstract
No abstract record available.
Inventors
- 👤 Wade W Allen
- 👤 Athol A Kelley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 04:14
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/14; G03B21/30
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1696831A
Cited
GB211169A
Cited
US2022903A
Cited
US1952522A
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US2234227A
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US2238762A
Cited
US2525552A
Cited
US2634652A
Cited
US2727135A
Cited
US2847902A
Cited
US2865249A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-03-05 | 1965-09-04 | 1966-03-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-03-05 | 1969-09-04 | 1970-03-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-03-05 | 1973-09-04 | 1974-03-06 | $7700.00 | Window Closed / Lapsed |