Patent US2021790A successfully refreshed from Google Patents.
US2021790A
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Antiglare device
Assignee: BUTLER KUHN CORP
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Filing: 1929-08-02
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Granted: 1935-11-19
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Expires: 1949-08-02
Abstract
No abstract record available.
Inventors
- 👤 Kuhn George
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 11:15
CPC Classifications
F; F21; F21V; F21V11/00; F21S; F21S41/00; F21S41/40; F21S41/43; F21S41/435; F21S41/47; F21W; F21W2107/00; F21W2107/10
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1938-11-18 | 1939-05-20 | 1939-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1942-11-18 | 1943-05-20 | 1943-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1946-11-18 | 1947-05-20 | 1947-11-19 | $7700.00 | Window Closed / Lapsed |