Legal Question in Business Law in Illinois

If you are talking about the need to register in Illinois, the Secretary of State takes a very broad view of what that is, so you'd have to be much more specific in terms of what the LLC is or may be doing, and the "general" rule is that unless it is solely a passive investor / holding company with no control or managerial powers of any kind, the Secretary of State considers any activity it pursues (for itself or a third party) as transacting business.