IL SB3536

Shifts responsibility for serving copies of large assessment complaints from the board of review to the complainant, requiring service on all taxing districts shown on the most recent tax bill for complaints seeking $100,000 or more in assessed value changes.

Requires complainants to include a certificate of service with their complaint filing; failure to include it results in waiver of the right to receive a change of $100,000 or more in assessed value for that tax year.

Creates new Section 16-57 allowing any taxing district with a revenue interest in a board of review complaint to intervene by filing a request within 30 days of being served notice of the complaint.

Requires intervention requests to be accompanied by a copy of the taxing district's governing board resolution authorizing its legal representative to intervene; incomplete requests are returned without extending the 30-day deadline.

Provides that taxing districts failing to intervene in the board of review proceeding waive their right to intervene in any subsequent appeal to the Property Tax Appeal Board.