Every private foundation liable for tax under section 4940 or 4948(a) shall file an annual return with respect to such tax on the form prescribed by the Internal Revenue Service for such purpose and shall include therein the information required by such form and the instructions issued with respect thereto.

Every person liable for tax imposed by sections 4941(a), 4942(a), 4943(a), 4944(a), 4945(a), 4955(a), 4958(a), 4959, or 4965(a), and every private foundation and every trust described in section 4947(a)(2) which has engaged in an act of self-dealing (as defined in section 4941(d)) (other than an act giving rise to no tax under section 4941(a)) shall file an annual return on Form 4720 and shall include therein the information required by such form and the instructions issued with respect thereto. In the case of any tax imposed by sections 4941(a), 4942(a), 4943(a), and 4944(a), the annual return shall be filed with respect to each act (or failure to act) for each year (or part thereof) in the taxable period (as defined in sections 4941 (e)(1), 4942(j)(1), 4943(d)(2), and 4944(e)(1)). In the case of a tax imposed by section 4945(a), 4955(a), 4958(a), or 4965(a), the annual return shall be filed with respect to each act for the year in which such act giving rise to liability occurred. In the case of a tax imposed by section 4959 on a hospital organization (as defined in § 1.501(r)-1(b)(18)), the annual return must include the required information for each of the organization's hospital facilities that failed to meet the requirements of section 501(r)(3) for the taxable year.

If a Form 4720 is filed by a private foundation or trust described in section 4947(a)(2) with respect to a transaction to which other persons are required to file under paragraph (b) of this section, such persons may by their signature designate such organization's Form 4720 (to the extent applicable) as their return for purposes of compliance with such paragraph. However, this paragraph shall not apply to a person whose taxable year is other than the taxable year of the foundation or trust.

For taxable years ending on or after December 31, 1975, every trust described in section 4947(a)(2) which is subject to any of the provisions of Chapter 42 as if it were a private foundation shall file an annual return on Form 5227. For taxable years beginning after December 31, 1980, every trust described in section 4947(a)(1) which is a private foundation shall file an annual return on Form 990-PF.

For taxable years beginning after December 31, 1977, every person liable for tax under section 4951, 4952, or 4953 (relating to taxes on self-dealing, taxable expenditures, and excess contributions involving black lung benefit trusts) shall file an annual return with respect to the tax on the form prescribed by the Internal Revenue Service for that purpose. The person liable for the tax shall include the information required by the form and its related instructions.