US3107728A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Down-hole heater
Assignee: Jersey Production Research Co
•
Filing: 1961-10-16
•
Granted: 1963-10-22
•
Expires: 1981-10-16
Abstract
No abstract record available.
Inventors
- 👤 Donald M Kehn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:41
CPC Classifications
E; E21; E21B; E21B36/00; E21B36/02
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US2382471A
Cited
US2506853A
Cited
US2707029A
Cited
US2675081A
Cited
US2941595A
Cited
US3010516A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1966-10-21 | 1967-04-22 | 1967-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1970-10-21 | 1971-04-22 | 1971-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1974-10-21 | 1975-04-22 | 1975-10-22 | $7700.00 | Window Closed / Lapsed |