(35 ILCS 200/16-135)
    Sec. 16-135. Omitted property; Notice provisions. In counties with 3,000,000 or more inhabitants, the owner of property and the executor, administrator, or trustee of a decedent whose property has been omitted in the assessment in any year or years or on which a tax for which the property was liable has not been paid, and the several taxing bodies interested therein, shall be given at least 30 days notice in writing by the board of appeals (until the first Monday in December 1998 and the board of review beginning the first Monday in December 1998 and thereafter) or county assessor of the hearing on the proposed assessments of the omitted property. The board or assessor shall have full power to examine the owner, or the executor, administrator, trustee, legatee, or heirs of the decedent, or other person concerning the ownership, kind, character, amount and the value of the omitted property.
    If the board determines that the property of any decedent was omitted from assessment during any year or years, or that a tax for which the property was liable, has not been paid, the board shall direct the county assessor to assess the property. However, if the county assessor, on his or her own initiative, makes such a determination, then the assessor shall assess the property. No charge for tax of previous years shall be made against any property prior to the date of ownership of the person owning the property at the time the liability for such omitted tax is first ascertained. Ownership as used in this Section refers to bona fide legal and equitable titles or interests acquired for value and without notice of the tax, as may appear by deed, deed of trust, mortgage, certificate of purchase or sale, or other form of contract. No such charge for tax of previous years shall be made against any property if:
        (1) the assessor failed to notify the board of review of an omitted assessment in
    
accordance with subsection (a-1) of Section 9-260 of this Code; or
        (2) the property was last assessed as unimproved, the owner of the property, gave
    
notice of subsequent improvements and requested a reassessment as required by Section 9-180, and reassessment of the property was not made within 16 months of receipt of that notice; or
        (3) the owner of the property gave notice as required by Section 9-265; or
        (4) the assessor received a building permit for the property evidencing that new
    
construction had occurred or was occurring on the property but failed to list the improvement on the tax rolls; or
        (5) the assessor received a plat map, plat of survey, ALTA survey, mortgage survey, or
    
other similar document containing the omitted property but failed to list the improvement on the tax rolls; or
        (6) the assessor received a real estate transfer declaration indicating a sale from an
    
exempt property owner to a non-exempt property owner but failed to list the property on the tax rolls; or
        (7) the property was the subject of an assessment appeal before the assessor or the
    
board of review that had included the intended omitted property as part of the assessment appeal and provided evidence of its market value.
    The assessment of omitted property by the county assessor may be reviewed by the board in the same manner as other assessments are reviewed under the provisions of this Code and when so reviewed, the assessment shall not thereafter be subject to review by any succeeding board.
    For the purpose of enforcing the provisions of this Code, relating to property omitted from assessment, the taxing bodies interested therein are hereby empowered to employ counsel to appear before the board or assessor (as the case may be) and take all necessary steps to enforce the assessment on the omitted property.
(Source: P.A. 96-1553, eff. 3-10-11.)