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US2520862A
Expired / Lapsed
US
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Air separation process
Assignee: Individual
•
Filing: 1946-10-07
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Granted: 1950-08-29
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Expires: 1966-10-07
Abstract
No abstract record available.
Inventors
- 👤 Judson S Swearingen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 01:13
CPC Classifications
F; F25; F25J; F25J3/00; F25J3/02; F25J3/04; F25J3/04006; F25J3/04012; F25J3/04018; F25J3/04109; F25J3/04115; F25J3/04127; F25J3/04139; F25J3/04248; F25J3/04284; F25J3/0429; F25J3/04303; F25J3/04375; F25J3/04381; F25J3/04406; F25J3/04412; F25J3/04521; F25J3/04563; F25J3/04575; F25J3/04593; F25J3/046; F25J3/04612; F25J2205/00; F25J2205/02; F25J2245/00; F25J2245/40; F25J2250/00; F25J2250/30; F25J2250/42; F25J2250/52
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1953-08-28 | 1954-02-27 | 1954-08-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-08-28 | 1958-02-27 | 1958-08-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-08-28 | 1962-02-27 | 1962-08-29 | $7700.00 | Window Closed / Lapsed |