A trademark lasts for as long as it continues to satisfy the five criteria for a valid trademark.
It is important to distinguish between registration of a trademark and the existence of the trademark. Rights incident to the registration of a trademark can be lost by failing to renew the registration or through cancellation of the registration by the USPTO. Abandonment or cancellation of the registration, however, does not necessarily terminate the trademark. A common law trademark may exist even if the registration is cancelled.