Section 15 is the one filing on a trademark docket with no deadline at all. Nothing lapses if it is never made. The registration continues, the renewals continue, and no notice is ever sent.
Which is exactly why it is the most commonly skipped filing in US trademark practice — and why skipping it tends to be discovered at the worst possible moment, in the middle of a dispute.
What it does
A Section 15 declaration makes a registration incontestable. In practical terms it closes off the two arguments most often used against a registration:
- That the mark is merely descriptive. Once incontestable, a challenger cannot argue the mark should never have registered because it describes the goods.
- That someone else used it first. Prior-use claims that were available before become unavailable after.
It is not absolute immunity. A mark can still be attacked as generic, as functional, as abandoned through non-use, or as obtained by fraud. But the ordinary challenges go away.
When it becomes available
After five consecutive years of continuous use in commerce following registration, provided there is no adverse decision and no pending proceeding involving the mark.
That five-year point sits inside the Section 8 window, which is why the two are almost always filed as one combined declaration. The marginal cost of adding Section 15 to a filing already being made is small; the cost of not having it is paid years later or not at all.
Why a docket should still track it
An obligation that never lapses is still worth surfacing, because the opportunity does close in a practical sense: once the Section 8 has been filed without it, the natural moment has passed, and it tends not to come back around until the next maintenance cycle four years later.
Sealvo treats Section 15 as optional rather than outstanding — it appears alongside the maintenance filing it should accompany, flagged as an opportunity rather than a deadline, because presenting it as something that will cause harm if missed would simply be untrue.