Alaska Stat. § 43.05.245
If a taxpayer fails to file a return or report required by this title in the time required by law or regulation, or makes an erroneous or fraudulent return, the department shall proceed to assess the license fees, tax, penalties, or interest and make a return from information that it obtains. An assessment or a return subscribed by the department in accordance with this section is presumed sufficient for all legal purposes. However, nothing prevents a taxpayer from presenting evidence or other information in an informal conference under AS 43.05.240 or in an appeal under AS 43.05.241 in order to rebut the presumed sufficiency of an assessment or return subscribed by the department, nor does the presumption of sufficiency alter the parties' respective burdens of proof once the taxpayer has presented evidence or other material information to rebut that presumption. The assessment of license fees, tax, penalties, or interest under this section occurs when the department issues a notice and demand for payment of the license fees, tax, penalties, or interest. The notice and demand for payment is issued when the notice and demand is delivered to the taxpayer in person or placed in the United States mail, addressed to the last known address of the taxpayer. Penalties and interest assessed under this title shall be collected in the same manner as provided in this title for the collection of tax or license fees.
AS 43.05.245