US2143974A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus for flowing wells
Assignee: Phillips Petroleum Co
•
Filing: 1935-04-22
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Granted: 1939-01-17
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Expires: 1955-04-22
Abstract
No abstract record available.
Inventors
- 👤 Herbert F Chapman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 23:36
CPC Classifications
E; E21; E21B; E21B43/00; E21B43/12; E21B43/121; E21B43/122; E21B43/123; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86389; Y10T137/86405; Y10T137/86413; Y10T137/86421; Y10T137/86429
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) | 1942-01-16 | 1942-07-18 | 1943-01-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-01-16 | 1946-07-18 | 1947-01-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-01-16 | 1950-07-18 | 1951-01-17 | $7700.00 | Window Closed / Lapsed |