805 ILCS 405/1
No person or persons shall conduct or transact business in this State under an assumed name, or under any designation, name or style, corporate or otherwise, other than the real name or names of the individual or individuals conducting or transacting such business, unless such person or persons shall file in the office of the County Clerk of the County in which such person or persons conduct or transact or intend to conduct or transact such business, a certificate setting forth the name under which the business is, or is to be, conducted or transacted, and the true or real full name or names of the person or persons owning, conducting or transacting the same, with the post office address or addresses of such person or persons and every address where such business is, or is to be, conducted or transacted in the county. The certificate shall be executed and duly acknowledged by the person or persons so conducting or intending to conduct the business.
Notice of the filing of such certificate shall be published in a newspaper of general circulation published within the county in which the certificate is filed. Such notice shall be published once a week for 3 consecutive weeks. The first publication shall be within 15 days after the certificate is filed in the office of the County Clerk. Proof of publication shall be filed with the County Clerk within 50 days from the date of filing the certificate. Upon receiving proof of publication, the clerk shall issue a receipt to the person filing such certificate but no additional charge shall be assessed by the clerk for giving such receipt. Unless proof of publication is made to the clerk, the certificate of registration of the assumed name is void.
If any person changes his name or his residence address or the address of any place of business in the county where such assumed name is being employed after filing a certificate, or if the name of a person is added to any business organization for which a certificate is on file, such person shall file an additional, duly acknowledged certificate in the office of the County Clerk of the county in which such person transacts business under an assumed name. The certificate shall set out the change or addition as the case may be. Such certificate shall also set out the post office address of the person. If any business organization for which such certificate has been filed in any county of this State shall remove its place of business to another county in this State or shall establish an additional location for doing business in another county of this State, a certificate shall be filed in the office of the County Clerk of such other county and notice of the filing of such certificate of a change or addition of a name shall be published and proof of publication made pursuant to the provisions of this section in the same manner as is provided for original certificates to do business under an assumed name.
A foreign person or foreign entity may not use an assumed or fictitious name in the conduct of its business to intentionally misrepresent the origin or location of the person or entity.
805 ILCS 405/1