26 U.S.C. § 4412

(a) Requirement Each person required to pay a special tax under this subchapter shall register with the official in charge of the internal revenue district— (1) his name and place of residence; (2) if he is liable for tax under subchapter A, each place of business where the activity which makes him so liable is carried on, and the name and place of residence of each person who is engaged in receiving wagers for him or on his behalf; and (3) if he is engaged in receiving wagers for or on behalf of any person liable for tax under subchapter A, the name and place of residence of each such person. (b) Firm or company Where subsection (a) requires the name and place of residence of a firm or company to be registered, the names and places of residence of the several persons constituting the firm or company shall be registered. (c) Supplemental information In accordance with regulations prescribed by the Secretary, the Secretary may require from time to time such supplemental information from any person required to register under this section as may be needful to the enforcement of this chapter.