The Illinois Notice of Filing is a legal document issued by the Illinois Secretary of State when a new business entity is formed. It is a notification to the public that the entity is now registered and can legally conduct business in the state of Illinois. The Notice of Filing contains information about the entity, such as its name, type, address, and registered agent. There are two types of Illinois Notice of Filing: one for domestic entities and one for foreign entities. The domestic entity Notice of Filing is required for any business created in the state of Illinois. The foreign entity Notice of Filing is required for any business created outside the state of Illinois that wishes to do business in the state.