Does a person's name in ALL CAPS signify a Sole Proprietor doing business with the Government?

No. There is no proof in any legal authority (i.e. act of congress or state legislature codified into statute or case law) that confirms the use of ALL CAPS changing the status of a person's unalienable and legal rights to a mere commercial status. This is a heavily promoted sovereign theory and though it seems peculiarly used in commercial and government administrative processes, there is no legal precedent to prove that is has any significance. There is much information on the internet that makes this theory seem plausible. However, a simple fact of law is if no clear act of congress, statute authorizing such a change in status, or case law confirms it's existence and/or authority, it cannot be proved. In fact, there are literally hundreds if not thousands of combined state and federal cases in which courts have struck down such theories and arguments as they have no basis in law.