Customer Name (please print):. Are you looking for an example of a Illinois Apostille?We can apostille an authorization letter signed and notarized in all 50 U.S. states, District of Columbia, and the U.S. Federal Government (USA Embassy). How to Submit Your Request. Learn how to fill out Form DS-4194 and mail your request or make an appointment at the Office of Authentications. Apostilles and authentication certificates validate the seal and signature of a Notary on a document so that it can be accepted in a foreign country. Illinois graduates who plan to work or further their education abroad may need to authenticate their degree(s) and transcripts with an apostille. 1. What is an Apostille and what is its purpose?