US2912013A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Duct construction
Assignee: IND PARK CORP
•
Filing: 1956-03-23
•
Granted: 1959-11-10
•
Expires: 1976-03-23
Abstract
No abstract record available.
Inventors
- 👤 Helmut A Freyholdt
- 👤 Fred M Mccown
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:38
CPC Classifications
F; F16; F16L; F16L9/00; F16L9/003; F16B; F16B2200/00; F16B2200/67; Y; Y10; Y10T; Y10T403/00; Y10T403/70; Y10T403/7062
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US1045740A
Cited
US1067189A
Cited
US1199357A
Cited
US1278343A
Cited
US1351613A
Cited
US1425953A
Cited
US1603627A
Cited
US2126499A
Cited
US2105784A
Cited
US2381178A
Cited
GB605534A
Cited
US2498753A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1962-11-09 | 1963-05-11 | 1963-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-11-09 | 1967-05-11 | 1967-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-11-09 | 1971-05-11 | 1971-11-10 | $7700.00 | Window Closed / Lapsed |