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Molten-Salt Electrolyte Unitized Regenerative Hydrogen-Halogen Fuel Cell with Anion Transfer

US 9,431,672 Lapsed on the fee record
OverviewFamilyAssignmentsSources & methods

Lapsed Aug 30, 2024 on the fee record · High confidence

Second maintenance fee unpaid; grace period ended.

Filed May 15, 2013 as application 13/894,599 · Granted Aug 30, 2016
Base term, 20 years from filing, plus 165 days of patent term adjustment (USPTO delay)
Today
Lapsed Aug 30, 2024
2013 2033
Clock starts
May 15, 2013
No longer in force
Aug 30, 2024
Granted
Aug 30, 2016
Term would have run to
Oct 27, 2033
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
165
Days of term adjustment
Read from the USPTO patent term adjustment record, not recalculated here.
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.
13
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 Oct 27, 2033: its 20-year base term plus 165 days of term 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 May 15, 2013, when this application, 13/894,599, was filedMay 15, 2033High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustment+165 days, USPTO patent term adjustment recordOct 27, 2033High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events1 of 3 maintenance fees paidlapsed Aug 30, 2024High confidence
Computed term endThe steps above, in orderAug 30, 2024High confidence

This family

US 9,834,827In force (reinstated)
Oct 2033
Oct 2033
US 9,431,672this patent
Aug 2024
Aug 2024
US 10,547,044In force
Sep 2036
Sep 2036
US 10,522,884In force
Jan 2034
Jan 2034
US 11,127,992In force
Oct 2033
Oct 2033
US 11,955,613In force
Oct 2033
Oct 2033
US 11,502,345In force
Apr 2033
Apr 2033
US 12,074,302In force
Aug 2033
Aug 2033
8 of 13 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 15, 2013
Reel 30423, frame 304
Datta, Ravindra; Martino, Drew J.Worcester Polytechnic InstituteAssignment of Assignor's Interest
Sep 17, 2025
Reel 72912, frame 604
Worcester Polytechnic InstituteThe Government of the United States of America as Represented by the Secretary of the NavyGovernment Interest Agreement

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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