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Method and System for Mixed Symmetric and Asymmetric Encryption of .zip Files

US 8,225,108 Term ended
OverviewFamilyAssignmentsSources & methods
Collateral for a security interest recorded Nov 23, 2020 (BMO Harris Bank N.A.).

Term ended Jun 25, 2026 · High confidence

Held by Pkware, Inc.
Filed Sep 20, 2004 as application 10/945,292 · Granted Jul 17, 2012
Base term plus 1075 days of patent term adjustment (USPTO delay)
Today
20 years from filing
Term ended Jun 25, 2026
2003 2026
Clock starts
Jul 16, 2003
Term ended
Jun 25, 2026
Granted
Jul 17, 2012
base term patent term adjustment after the term ends fee events Updated Nov 14, 2026 · includes USPTO assignment & status data published Nov 14, 2026 and grant & fee data published Nov 10, 2026 (weekly) · how we know
1,075
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
None
Terminal disclaimer
No disclaimer on this record.
3 of 3
Maintenance fees paid
Three maintenance fees fall due, at 3.5, 7.5 and 11.5 years from grant. This counts the ones the record shows paid.
51
Family applications on record here
Applications sharing this one's continuity chain whose file history this site holds. The family may have others.

This patent's term runs 1075 days past its 20-year base term on prosecution delay. All three maintenance fees were paid, so no fee lapse ended it. Confidence: High. from the record

How we calculated this date

One row per rule, each showing its own input and what it did to the date. A step we could not verify says so instead of resolving itself.
StepInputDate after this stepConfidence
Base term, 20 years from filingClock starts Jul 16, 2003, when application 10/620,960, the earliest non-provisional in its chain, was filed (this one was filed Sep 20, 2004)Jul 16, 2023High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+1075 days, USPTO patent term adjustment recordJun 25, 2026High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events3 of 3 maintenance fees paidterm endedHigh confidence
Computed term endThe steps above, in orderJun 25, 2026High confidence

This family

US 6,879,988Term ended
Dec 2021
Dec 2021
Application 10/620,960Abandoned
not computed
not computed
US 8,090,942Term ended
no later than Dec 2021
no later than Dec 2021
US 8,225,108this patent
Jun 2026
Jun 2026
US 7,793,099Term ended
Jun 2025
Jun 2025
Application 10/946,271Abandoned
not computed
not computed
Application 10/945,475Abandoned
not computed
not computed
US 7,895,434In force
Feb 2027
Feb 2027
8 of 51 applications in this family shown, earliest filings first. The applications whose file history this site holds. The family may have others.

Assignments

Assignment documents as recorded at the USPTO, oldest first, with the reel and frame each was recorded at. A recorded assignment is a filed document, not a statement of current ownership, and the absence of a later one is not evidence that the last one still stands.
RecordedAssignorAssigneeConveyance
Jan 17, 2005
Reel 15599, frame 586
Peterson, James C.Pkware, Inc.Assignment of Assignor's Interest
Aug 18, 2009
Reel 23107, frame 510
Pkware, Inc.Maranon Capital, L.P., as AgentSecurity Agreement
Aug 19, 2009
Reel 23107, frame 952
Pkware, Inc.Maranon Capital, L.P., as AgentSecurity Agreement
Dec 23, 2010
Reel 25525, frame 230
Maranon Capital, L.P., as AgentPkware, Inc.Release of Security Interest
Nov 23, 2020
Reel 54501, frame 694
Pkware, Inc.BMO Harris Bank N.A.Patent Security Agreement
Jun 2, 2025
Reel 71279, frame 876
Pkware, Inc.Audax Private Debt LLC, as AgentSecurity Interest
Jun 3, 2025
Reel 71497, frame 411
BMO Bank N.A. (F/K/A BMO Harris Bank N.A.), as AgentPkware, Inc.Release of Security Interest Recorded at Reel/Frame 054501/0694

Sources

Google Patents · The patent document at USPTO · Assignment records at USPTO

USPTO account required: This application in Patent Center · USPTO's maintenance fee lookup

Maintenance fee events come from USPTO's own fee records. Its fee lookup asks for the patent number and the application number.

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