Md. Code, Tax-Prop. § 8-417

(a) In this section, “escaped property” means any property that: (1) is subject to assessment for property tax purposes; and (2) has not been assessed. (b) Notwithstanding § 8-418 of this subtitle, after it is discovered, escaped property is assessed in the same manner as other similar property is assessed. (c) (1) When escaped property is assessed it is placed on the assessment roll and tax roll and is subject to property tax for: (i) the current taxable year; and (ii) not more than 3 previous taxable years. (2) The county tax imposition for each county or municipal corporation tax imposition for each municipal corporation shall be deemed to have covered all property that was not assessed but which should have been assessed for the year that any county or municipal corporation tax was imposed. (d) If personal property is assessed at less than its value as a result of the owner inaccurately reporting the cost or other information as to the property, the underassessed part of the property shall be treated as escaped property.