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US

Fenfluramine Compositions and Methods of Preparing the Same

US 11,634,377 In force
OverviewFamilyAssignmentsSources & methods

Also listed on Zogenix, Inc., an earlier holder on the record. The recorded assignments below show how it moved.

Term ends Dec 20, 2036 · High confidence

Filed Jan 27, 2021 as application 17/159,367 · Granted Apr 25, 2023
Base term, 20 years from filing
Today
20 years from filing
2016 2036
Clock starts
Dec 20, 2016
Term ends
Dec 20, 2036
Granted
Apr 25, 2023
base term 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
None
Term adjustment
No prosecution delay on this record.
None
Terminal disclaimer
No disclaimer on this record.
1 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.

This patent's term is its 20-year base term, with no adjustment for prosecution delay. 1 of 3 maintenance fees is paid so far. 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 Dec 20, 2016, when application 15/385,525, the earliest non-provisional in its chain, was filed (this one was filed Jan 27, 2021)Dec 20, 2036High 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 events1 of 3 maintenance fees paidIn forceHigh confidence
Computed term endThe steps above, in orderDec 20, 2036High confidence

This family

US 10,351,509In force
Dec 2036
Dec 2036
US 10,947,183In force
Dec 2036
Dec 2036
US 11,634,377this patent
Dec 2036
Dec 2036
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 26, 2021
Reel 55422, frame 210
Londesbrough, Derek; Andersen, MarcZogenix International LimitedAssignment of Assignor's Interest
Jun 6, 2025
Reel 71510, frame 1
Londesbrough, Derek; Anderson, MarcZogenix International LimitedCorrective Assignment to Correct the Assignee Address Previously Recorded at Reel: 55422 Frame: 210. Assignor(S) Hereby Confirms the Assignment .
Jul 21, 2025
Reel 73731, frame 181
Zogenix International LimitedZogenix International LimitedAssignee Change of Address

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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