US3507645A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Separation process
Assignee: Shell USA Inc
•
Filing: 1968-02-23
•
Granted: 1970-04-21
•
Expires: 1988-02-23
Abstract
No abstract record available.
Inventors
- 👤 Ernst L T M Spitzer
- 👤 Alun Gabriel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:02
CPC Classifications
C; C01; C01G; C01G1/00; C01G1/06; C01G3/00; C01G3/003; C01G49/00; C01G49/0009; C01G51/00; C01G51/01; C01G53/00; C01G53/01; C22; C22B; C22B3/00; C22B3/20; C22B3/26; C22B3/28; C22B3/32; C22B3/34; Y; Y02; Y02P; Y02P10/00; Y02P10/20
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US3251646A
Cited
US3369876A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1973-04-20 | 1973-10-20 | 1974-04-21 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-04-20 | 1977-10-20 | 1978-04-21 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-04-20 | 1981-10-20 | 1982-04-21 | $7700.00 | Window Closed / Lapsed |