US2442432A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Sewage treatment
Assignee: Graver Energy Systems Inc
•
Filing: 1942-08-22
•
Granted: 1948-06-01
•
Expires: 1962-08-22
Abstract
No abstract record available.
Inventors
- 👤 Frank D Prager
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 23:18
CPC Classifications
C; C02; C02F; C02F3/00; C02F3/02; C02F3/04; Y; Y02; Y02W; Y02W10/00; Y02W10/10
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-06-01 | 1951-12-01 | 1952-06-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-06-01 | 1955-12-01 | 1956-06-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-06-01 | 1959-12-01 | 1960-06-01 | $7700.00 | Window Closed / Lapsed |