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US3390224A Expired / Lapsed US ⏱️ 0.0 years remaining

Adjustable underground shell

Assignee: NEW ENGLAND REALTY CO
•
Filing: 1966-09-28
•
Granted: 1968-06-25
•
Expires: 1986-09-28
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Abstract

No abstract record available.

Inventors

  • 👤 David L Wyatt

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 20:13
CPC Classifications
H; H02; H02G; H02G9/00; H02G9/10; Y; Y10; Y10T; Y10T137/00; Y10T137/6851; Y10T137/6966; Y10T137/6991; Y10T137/6995; Y10T137/7017

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US407955A Cited
US1265767A Cited
US1280388A Cited
US1408982A Cited
US1894381A Cited
US2097394A Cited
US2100721A Cited
US3101207A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1971-06-25 1971-12-25 1972-06-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1975-06-25 1975-12-25 1976-06-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1979-06-25 1979-12-25 1980-06-25 $7700.00 Window Closed / Lapsed

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