35 ILCS 5/503
2021 Illinois Compiled Statutes|Chapter 35 - REVENUE|35 ILCS 5/ - Illinois Income Tax Act.|Article 5 - Records, Returns And Notices

 (from Ch. 120, par. 5-503)Sec. 503. Signing of returns and notices.(a) Signature presumed authentic. The fact that an individual's name  is signed to a return or notice shall be prima facie evidence for all  purposes that such document was actually signed by such individual. If a  return is prepared by an income tax return preparer for a taxpayer, that  preparer shall sign the return as the preparer of that return and include his or her PTIN, as defined in the   State Tax Preparer Oversight Act, on the return.  If a return is transmitted to the Department electronically, the  Department may presume that the electronic return originator has obtained  and is transmitting a valid signature document pursuant to the rules  promulgated by the Department for the electronic filing of tax returns, or  the Department may authorize electronic return originators to maintain the  signature documents and associated documentation, subject to the Department's  right of inspection at any time without notice, rather than transmitting those  documents to the Department, and  the Department may process the return.(b) Corporations. A return or notice required of a corporation shall  be signed by the president, vice-president, treasurer or any other officer  duly authorized so to act or, in the case of a limited liability company, by  a manager or member. In the case of a return or notice made for a  corporation by a fiduciary pursuant to the provisions of Section 502(b)(4), such fiduciary shall sign such document. The fact that an  individual's name is signed to a return or notice shall be prima facie  evidence that such individual is authorized to sign such document on behalf  of the corporation.(c) Partnerships. A return or notice of a partnership shall be signed  by any one of the partners or, in the case of a limited liability company, by  a manager or member. The fact that a partner's name is signed to a  return or notice shall be prima facie evidence that such individual is  authorized to sign such document on behalf of the partnership or limited  liability company.(d) Joint fiduciaries. A return or notice signed by one of two or  more joint fiduciaries will comply with the requirements of this Act. The  fact that a fiduciary's name is signed to such document shall be prima  facie evidence that such fiduciary is authorized to sign such document on  behalf of the person from whom it is required.(e) Failure to sign a return.  If a taxpayer fails to sign a return  within 30 days after proper notice and demand for signature by  the  Department, the return shall be considered valid and any amount shown to be  due on the return shall be deemed assessed.  Any overpayment of tax shown  on the face of an unsigned return shall be considered forfeited if after  notice and demand for signature by the Department the taxpayer fails to  provide a signature and 3 years have passed from the date the return was  filed.  An overpayment of tax refunded to a taxpayer whose return was  filed electronically shall be considered an erroneous refund under Section  912 of this Act if, after proper notice and demand by the  Department, the taxpayer fails to provide a required signature document.  A notice and demand for signature in the case of a return  reflecting an overpayment may be made by first class mail.  This subsection  (e) shall apply to all returns filed pursuant to the Illinois Income Tax Act  since 1969.  (Source: P.A. 99-641, eff. 1-1-17.)