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Tissue engineering scaffold comprising polyurethane material having voids interconnected by pores

US 8,168,431 Lapsed on the fee record
OverviewSources & methods

Lapsed May 1, 2020 on the fee record · From the USPTO record

Second maintenance fee unpaid; grace period ended.

Named at grant Cellology Limited · find this owner
Filed Nov 14, 2008 as application 12/271,336 · Granted May 1, 2012
Base term, 20 years from filing, plus 560 days of patent term adjustment (USPTO delay)
Today
Lapsed May 1, 2020
2000 2026
Clock starts
May 8, 2000
No longer in force
May 1, 2020
Granted
May 1, 2012
Term would have run to
Nov 19, 2021
base term patent term adjustment 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
560
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 2
Maintenance fees paid
Two maintenance fees can end this term early, the ones due 3.5 and 7.5 years from grant; the third one's grace period runs past the term end. This counts the ones the record shows paid.

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 May 8, 2000, when the earliest non-provisional application in its chain was filed (this one was filed Nov 14, 2008); a parent in its chain could not be resolved (the next row)May 8, 2020High confidence
Continuity chainA parent in the chain could not be resolveddated from this application's own claimMedium confidence
Patent term adjustment+560 days, USPTO patent term adjustment recordNov 19, 2021High confidence
Terminal disclaimer capNone on recordno cap appliedHigh confidence
Patent term extensionNone on fileno changeHigh confidence
Fee events1 of 2 maintenance fees paidlapsed May 1, 2020High confidence
Computed term endThe steps above, in orderMay 1, 2020From the USPTO record

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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