Preparation of metal chalcogenide nanoparticles and nanocomposites therefrom
US 7,264,874 Lapsed on the fee recordLapsed Sep 4, 2019 on the fee record · From the USPTO record
20-year base term ended Dec 22, 2024
Third maintenance fee unpaid; grace period ended.
Dec 22, 2004
Sep 4, 2019
Sep 4, 2007
Jul 25, 2025
How we calculated this date
| Step | Input | Date after this step | Confidence |
|---|---|---|---|
| Base term, 20 years from filing | Clock starts Dec 22, 2004, when this application, 11/020,620, was filed | Dec 22, 2024 | High confidence |
| Continuity chain | Every parent in the chain resolved | no change | High confidence |
| Patent term adjustment | +215 days, USPTO patent term adjustment record | Jul 25, 2025 | High confidence |
| Terminal disclaimer cap | None on record | no cap applied | High confidence |
| Patent term extension | None on file | no change | High confidence |
| Fee events | 2 of 3 maintenance fees paid | lapsed Sep 4, 2019 | High confidence |
| Computed term end | The steps above, in order | Sep 4, 2019 | From 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
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