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US2554814A
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Assignee: Paper Patents Co
•
Filing: 1945-05-21
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Granted: 1951-05-29
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Expires: 1965-05-21
Abstract
No abstract record available.
Inventors
- 👤 John B Catlin
- 👤 John C Wollwage
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:24
CPC Classifications
B; B32; B32B; B32B27/00; B01; B01D; B01D39/00; B01D39/14; B01D39/16; B01D39/18; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24355; Y10T428/24446; Y10T428/24455; Y10T428/24463; Y10T428/24802; Y10T428/24826; Y10T428/249921; Y10T428/249953; Y10T428/249962; Y10T428/249964; Y10T428/249965; Y10T428/249966; Y10T428/31504; Y10T428/31971; Y10T428/31975; Y10T428/31978; Y10T428/31982
Claims Analysis
Total Claims: 0
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US1915339A
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US2354395A
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1954-05-28 | 1954-11-27 | 1955-05-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-05-28 | 1958-11-27 | 1959-05-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-05-28 | 1962-11-27 | 1963-05-29 | $7700.00 | Window Closed / Lapsed |