Patent US3516931A successfully refreshed from Google Patents.
US3516931A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process of treating acid mine water
Assignee: Barnes and Tucker Co
•
Filing: 1968-10-18
•
Granted: 1970-06-23
•
Expires: 1988-10-18
Abstract
No abstract record available.
Inventors
- 👤 Joseph J Birch
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 15:10
CPC Classifications
C; C02; C02F; C02F9/00; C02F2101/00; C02F2101/10; C02F2101/20
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1310382A
Cited
US773395A
Cited
US785312A
Cited
US1248329A
Cited
US1254009A
Cited
US2810633A
Cited
US3218252A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-06-22 | 1973-12-22 | 1974-06-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-06-22 | 1977-12-22 | 1978-06-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-06-22 | 1981-12-22 | 1982-06-23 | $7700.00 | Window Closed / Lapsed |