Illumination Sources and Subjects Having Distinctly Matched and Mismatched Narrow Spectral Bands
US 8,551,683 Term endedTerm ended Jul 27, 2025 · High confidence
20-year base term ended Feb 11, 2025
USPTO later recorded it as expired for non-payment on Nov 10, 2025.
Feb 11, 2005
Jul 27, 2025
Oct 8, 2013
How we calculated this date
| Step | Input | Date after this step | Confidence |
|---|---|---|---|
| Base term, 20 years from filing | Clock starts Feb 11, 2005, when the earliest non-provisional application in its chain was filed (this one was filed May 3, 2011) | Feb 11, 2025 | High confidence |
| Continuity chain | Every parent in the chain resolved | no change | High confidence |
| Patent term adjustment | +166 days, USPTO patent term adjustment record | Jul 27, 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 2 maintenance fees paid | term ended | High confidence |
| USPTO status record | Recorded as expired for non-payment on Nov 10, 2025, after the term ended | no change | High confidence |
| Computed term end | The steps above, in order | Jul 27, 2025 | High 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.