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Methods for the Synthesis of Unsymmetrical Cycloakyl Substituted Xanthines

US 8,501,941 Lapsed on the fee record
OverviewFamilyAssignmentsSources & methods

Lapsed Aug 6, 2025 on the fee record · High confidence

Third maintenance fee unpaid; grace period ended.

Filed May 17, 2012 as application 13/474,258 · Granted Aug 6, 2013
Base term, 20 years from filing
Today
Lapsed Aug 6, 2025
2006 2026
Clock starts
Feb 27, 2006
No longer in force
Aug 6, 2025
Granted
Aug 6, 2013
Term would have run to
Feb 27, 2026
base term after the term ends 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
None
Term adjustment
No prosecution delay on this record.
None
Terminal disclaimer
No disclaimer on this record.
2 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.
3
Family applications on record here
Applications sharing this one's continuity chain whose file history this site holds. The family may have others.

Its term would have run to Feb 27, 2026: its 20-year base term, with no adjustment for prosecution delay. 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 Feb 27, 2006, when application 11/362,390, the earliest non-provisional in its chain, was filed (this one was filed May 17, 2012)Feb 27, 2026High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustmentNone on fileno changeHigh confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events2 of 3 maintenance fees paidlapsed Aug 6, 2025High confidence
Computed term endThe steps above, in orderAug 6, 2025High confidence

This family

US 7,598,379In force
Dec 2027
Dec 2027
US 8,420,813Lapsed on the fee record
Apr 2025
Apr 2025
US 8,501,941this patent
Aug 2025
Aug 2025
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
Feb 1, 2013
Reel 29737, frame 130
Forest Laboratories Holdings LimitedDogwood Pharmaceuticals, Inc.Assignment of Assignor's Interest
Feb 1, 2013
Reel 29736, frame 958
Clinical Data, Inc.Dogwood Pharmaceuticals, Inc.Assignment of Assignor's Interest
Feb 1, 2013
Reel 29737, frame 43
Dogwood Pharmaceuticals, Inc.Forest Laboratories Holdings LimitedAssignment of Assignor's Interest
Mar 19, 2013
Reel 30045, frame 915
Forest Laboratories Holdings LimitedDogwood Pharmaceuticals, Inc.Corrective Assignment to Correct the Execution Date of the Previously Recorded Assignment from December 31, 2011 to March 15, 2013 Previously Recorded on Reel 029737 Frame 0130. Assignor(S) Hereby Confirms the the Execution Date of the Original Assignment Was Incorrectly Dated December 31, 2011.
Jun 26, 2018
Reel 46208, frame 691
Dogwood Pharmaceuticals, Inc.Allergan Sales, LLCMerger

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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