Patent US3440523A successfully refreshed from Google Patents.
US3440523A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for electromagnetic determination of the position of boundaries of and discontinuities in a geological formation
Assignee: IFP Energies nouvelles
•
Filing: 1966-03-28
•
Granted: 1969-04-22
•
Expires: 1986-03-28
Abstract
No abstract record available.
Inventors
- 👤 Robert Gabillard
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 22:55
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/18; G01V3/30
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2139460A
Cited
US2661466A
Cited
US2653220A
Cited
US2657380A
Cited
US3168694A
Cited
US3286163A
Cited
US3350634A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-04-21 | 1972-10-21 | 1973-04-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-04-21 | 1976-10-21 | 1977-04-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-04-21 | 1980-10-21 | 1981-04-22 | $7700.00 | Window Closed / Lapsed |