Patent US3472589A successfully refreshed from Google Patents.
US3472589A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Overhead projector
Assignee: Charles Beseler Co
•
Filing: 1965-10-23
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Granted: 1969-10-14
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Expires: 1985-10-23
Abstract
No abstract record available.
Inventors
- 👤 Philip M Field
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 13:57
CPC Classifications
G; G03; G03B; G03B21/00; G03B21/132; Y; Y10; Y10S; Y10S353/00; Y10S353/06
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3191491A
Cited
GB990930A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-10-13 | 1973-04-14 | 1973-10-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-10-13 | 1977-04-14 | 1977-10-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-10-13 | 1981-04-14 | 1981-10-14 | $7700.00 | Window Closed / Lapsed |