US2159488A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Perforated membrane
Assignee: Johns Manville Corp
•
Filing: 1935-08-01
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Granted: 1939-05-23
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Expires: 1955-08-01
Abstract
No abstract record available.
Inventors
- 👤 John S Parkinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:28
CPC Classifications
E; E04; E04B; E04B1/00; E04B1/62; E04B1/74; E04B1/82; E04B1/84; E04B1/8409; E04B2001/742; E04B2001/747; E04B2001/8263; E04B2001/8281; E04B2001/8457; E04B2001/8476; E04B2001/848
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) | 1942-05-22 | 1942-11-21 | 1943-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-05-22 | 1946-11-21 | 1947-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-05-22 | 1950-11-21 | 1951-05-23 | $7700.00 | Window Closed / Lapsed |