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US3520472A Expired / Lapsed US ⏱️ 0.0 years remaining

Tamper-proof envelope

Assignee: Individual
•
Filing: 1968-07-05
•
Granted: 1970-07-14
•
Expires: 1988-07-05
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Abstract

No abstract record available.

Inventors

  • 👤 Zdzislaw Kukulski

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 13:13
CPC Classifications
B; B65; B65D; B65D27/00; B65D27/12; B65D27/30

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

CH24710A Cited
US942420A Cited
US1800143A Cited
US2756875A Cited
US3120336A Cited
US3439868A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1973-07-13 1974-01-12 1974-07-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1977-07-13 1978-01-12 1978-07-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1981-07-13 1982-01-12 1982-07-14 $7700.00 Window Closed / Lapsed

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