D.C. Mun. Regs. tit. 9, r. 9-152
Each person (except a registered or practical nurse, a corporation, or an unincorporated business) who has been exempted from the unincorporated business tax either because that person's trade or business cannot by law, custom, or ethics be incorporated or, because more than eighty percent (80%) of the gross income of that trade or business is derived from personal services actually rendered by the individual or members of the partnership or other entity, and in which capital is not a material income-producing factor, who engages in or conducts in the District of Columbia a trade or business, is required to apply for and obtain annually a trade, business, or professional license.
To enable the Deputy Chief Financial Officer to make a determination of the liability of any person for obtaining a license under the provisions of Title 14 of the Act, the Deputy Chief Financial Officer shall be authorized to require that person to furnish any information that the Deputy Chief Financial Officer may need to make a determination.
Application for license shall be filed with the Deputy Chief Financial Officer prior to December 1st of each year for the succeeding calendar year on forms to be furnished by the Deputy Chief Financial Officer.
Each application shall be accompanied by the license fee of one hundred dollars ($ 100).
Individuals working for others on a salary basis shall not be required to obtain a license pursuant to this section for their work as employees, nor shall registered or practical nurses be required to obtain a license.
Each person required to obtain a license who commences to engage in or conduct a trade, business, or profession on or after January 1, 1957, shall obtain a license within sixty (60) days after the date of commencement of the trade, business, or profession in the District of Columbia.
Licenses issued under Title 14 of the Act are in addition, and not in lieu of, all other licenses and permits required by law.
All licenses issued under Title 14 of the Act and this section shall be in effect for the duration of the calendar year for which issued, unless revoked as provided in Title 14 of the Act.
All licenses issued under this section shall expire at midnight on the 31st day of December each year.
No license may be transferred to any person.
D.C. Mun. Regs. tit. 9, r. 9-152