Patent US1182602A successfully refreshed from Google Patents.
Patent US3368636A successfully refreshed from Google Patents.
US3368636A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of drilling a hole in a permeable underground formation and drilling fluid suitable for carrying out said method
Assignee: Shell USA Inc
•
Filing: 1964-11-30
•
Granted: 1968-02-13
•
Expires: 1984-11-30
Abstract
No abstract record available.
Inventors
- 👤 Jongbloed Lodewijk J Schmit
- 👤 Nicolaas H Van Lingen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 17:26
CPC Classifications
C; C09; C09K; C09K8/00; C09K8/02; C09K8/04; C09K8/14; C09K8/18; C09K8/22; C09K8/24; E; E21; E21B; E21B21/00
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2259875A
Cited
US2380156A
Cited
US2812161A
Cited
US3040822A
Cited
US3223185A
Cited
US3221825A
Cited
US3158210A
Cited
US3228469A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1971-02-12 | 1971-08-14 | 1972-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-02-12 | 1975-08-14 | 1976-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-02-12 | 1979-08-14 | 1980-02-13 | $7700.00 | Window Closed / Lapsed |