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US

Method for Obtaining Pure Tetrahydrocannabinol

US 7,923,558 In force
OverviewFamilyAssignmentsSources & methods

Term ends Apr 21, 2027 · High confidence

Held by Purisys LLC
Filed May 10, 2007 as application 11/571,864 · Granted Apr 12, 2011
Base term plus 1006 days of patent term adjustment (USPTO delay)
Today
20 years from filing
2004 2027
Clock starts
Jul 19, 2004
Term ends
Apr 21, 2027
Granted
Apr 12, 2011
base term patent term adjustment fee events Updated Nov 15, 2026 · includes USPTO assignment & status data published Nov 15, 2026 and grant & fee data published Nov 10, 2026 (weekly) · how we know
1,006
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.
2
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 1006 days past its 20-year base term on prosecution delay. All three maintenance fees are recorded paid; no more fees are due. 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 19, 2004, when application PCT/CH2004/000458, the earliest non-provisional in its chain, was filed (this one was filed May 10, 2007)Jul 19, 2024High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+1006 days, USPTO patent term adjustment recordApr 21, 2027High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events3 of 3 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderApr 21, 2027High confidence

This family

US 7,923,558this patent
Apr 2027
Apr 2027
1 of 2 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
May 10, 2007
Reel 19273, frame 476
Arslantas, Enver; Weigl, UlrichCilag Ltd.Assignment of Assignor's Interest
Jul 19, 2016
Reel 39189, frame 769
Noramco GmbHCerberus Business Finance, LLCSecurity Interest
Jul 19, 2016
Reel 39390, frame 618
Cilag AGNoramco GmbHAssignment of Assignor's Interest
Dec 4, 2019
Reel 51175, frame 606
Noramco GmbHNoramco, Inc.Assignment of Assignor's Interest
Dec 31, 2019
Reel 51455, frame 724
Noramco, Inc.Noramco, LLCEntity Conversion
Jan 7, 2020
Reel 51433, frame 718
Noramco, LLCPurisys LLCAssignment of Assignor's Interest
Mar 23, 2020
Reel 52207, frame 503
Purisys LLCCerberus Business Finance, LLC, as Collateral AgentAssignment of Security Interest - Patents
May 1, 2026
Reel 74545, frame 764
Cerberus Business Finance, LLCPurisys LLCRelease of Security Interest

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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