The act of March 9, 1945, (15 U.S.C. 1011-15) which declares a general policy that Federal laws which regulate or affect business and commerce are not to be interpreted as affecting the insurance business unless specifically provided for. Also known as the McCarran-Wiler Bill (S. 1508) and Public Law 15. Prior to a Supreme Court decision in 1944 insurance was not considered a matter of commerce and thus not subject to Federal law. When the Supreme Court found insurance to be a matter of commerce it became necessary to clarify the effect of existing Federal law on it. The Act has the effect of leaving regulation of insurance to the States unless specifically undertaken in Federal law.