US2810439A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Well head attachment for operating tools in a well under pressure
Assignee: Individual
•
Filing: 1955-05-11
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Granted: 1957-10-22
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Expires: 1975-05-11
Abstract
No abstract record available.
Inventors
- 👤 Mccullough Otis Johnson
- 👤 Lester W Toelke
- 👤 Ira J Mccullough
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 16:05
CPC Classifications
E; E21; E21B; E21B33/00; E21B33/02; E21B33/03; E21B33/068; E21B33/072; B; B66; B66D; B66D1/00; B66D1/28; B66D1/36; B66D1/39
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) | 1960-10-21 | 1961-04-22 | 1961-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-10-21 | 1965-04-22 | 1965-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-10-21 | 1969-04-22 | 1969-10-22 | $7700.00 | Window Closed / Lapsed |