Cation-Exchange Displacement Chromatography Process and Cationic Organic Compounds for Use as Displacer Compounds in Cation-Exchange Displacement Chromatography Process
US 7,632,409 In forceTerm ends Apr 14, 2027 · Medium confidence
20-year base term ended Nov 4, 2025
Why Medium: A parent in the chain could not be resolved.
Nov 4, 2005
Apr 14, 2027
Dec 15, 2009
How we calculated this date
| Step | Input | Date after this step | Confidence |
|---|---|---|---|
| Base term, 20 years from filing | Clock starts Nov 4, 2005, when the earliest non-provisional application in its chain was filed (this one was filed Oct 23, 2006); a parent in its chain could not be resolved (the next row) | Nov 4, 2025 | High confidence |
| Continuity chain | A parent in the chain could not be resolved | dated from this application's own claim | Medium confidence |
| Patent term adjustment | +526 days, USPTO patent term adjustment record | Apr 14, 2027 | 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 | 3 of 3 maintenance fees paid | In force | High confidence |
| Computed term end | The steps above, in order | Apr 14, 2027 | Medium 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.
In force means the term is running and no lapse is on record. It is not a finding that the patent is valid.