US3429131A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Pipeline trenching apparatus
Assignee: Individual
•
Filing: 1967-03-22
•
Granted: 1969-02-25
•
Expires: 1987-03-22
Abstract
No abstract record available.
Inventors
- 👤 Charles F Martin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 15:37
CPC Classifications
E; E02; E02F; E02F5/00; E02F5/02; E02F5/10; E02F5/104; E02F5/105; E02F3/00; E02F3/04; E02F3/88; E02F3/90; E02F3/92; E02F3/9212; E02F3/9225; E02F3/9231; E02F5/04; E02F5/108; E02F5/109
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2417313A
Cited
US2755632A
Cited
US3004392A
Cited
US3103790A
Cited
US3238734A
Cited
US3368358A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-02-25 | 1972-08-26 | 1973-02-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-02-25 | 1976-08-26 | 1977-02-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-02-25 | 1980-08-26 | 1981-02-25 | $7700.00 | Window Closed / Lapsed |