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Persistent Vortex Generating High Regression Rate Solid Fuel Grain for A Hybrid Rocket Engine

US 10,309,346 Surrendered on reissue
OverviewSources & methods

Surrendered on reissue Jan 2, 2024 · High confidence

Surrendered on reissue Jan 2, 2024 · its term and maintenance fees continue in US RE49,778.

Held by Firehawk Aerospace, Inc.
Filed Jan 11, 2018 as application 15/867,852 · Granted Jun 4, 2019
Base term, 20 years from filing
Today
Surrendered Jan 2, 2024
2008 2028
Clock starts
Mar 21, 2008
No longer in force
Jan 2, 2024
Granted
Jun 4, 2019
Term would have run to
Mar 21, 2028
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.
No effect
Terminal disclaimer
Resolved from the filed document, referencing US 9,890,091, to Mar 21, 2028. The term already ends on or before that date, so the cap shortened nothing.
1 of 3
Maintenance fees paid
Fees paid on this patent before its reissue. Those after fall due on the reissue, which carries the term on.

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.
Step Input Date after this step Confidence
Base term, 20 years from filingClock starts Mar 21, 2008, when the earliest non-provisional application in its chain was filed (this one was filed Jan 11, 2018)Mar 21, 2028High confidence
Continuity chainEvery parent in the chain resolvedno changeHigh confidence
Patent term adjustmentNone on fileno changeHigh confidence
Terminal disclaimer capDisclaimer resolved from the filed document (refs US 9,890,091)resolves to Mar 21, 2028, no earlier than this term, so no changeHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events1 of 2 maintenance fees paidno changeHigh confidence
ReissueUS RE49,778 issued Jan 2, 2024, and this patent's term continues in it (35 U.S.C. 251, 252)surrendered Jan 2, 2024High confidence
Surrendered on reissueThe steps above, in orderJan 2, 2024High confidence

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.

Not on this page: the patent's family, its recorded assignments and its citation count. USPTO's assignment records, linked above, list every recorded assignment.

Every date shows its work: the base term, any term adjustment or extension, any disclaimer cap, and the maintenance fee record, each with a confidence tier. How this record was built

Computed patent terms end on the dates shown. Related patents and pending applications may cover overlapping subject matter.

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