US2191652A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of sealing earth formations
Assignee: United States Gypsum Co
•
Filing: 1938-08-12
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Granted: 1940-02-27
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Expires: 1958-08-12
Abstract
No abstract record available.
Inventors
- 👤 Jr Andrew C Hamilton
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 09:48
CPC Classifications
C; C04; C04B; C04B28/00; C04B28/14; C09; C09K; C09K8/00; C09K8/42; C09K8/46; E; E02; E02D; E02D19/00; E02D19/06; E02D19/12; E02D19/16
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1943-02-26 | 1943-08-28 | 1944-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-02-26 | 1947-08-28 | 1948-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-02-26 | 1951-08-28 | 1952-02-27 | $7700.00 | Window Closed / Lapsed |