26 CFR § 301.6501(n)-1 - Special rules for chapter 42 and similar taxes.
(a) Return filed by private foundation, plan, trust, or other organization.
(1) A return filed by a private foundation, plan, trust, or other organization (as the case may be) with respect to any act giving rise to a tax imposed by chapter 42 (other than a tax imposed by section 4940), or by section 4975 shall be considered, for purposes of section 6501, to be the return of all persons required to file a return with respect to any such tax arising from such act, notwithstanding that all such persons have not signed the return. In the case of a private foundation that files a Form 990-PF (or a Form 5227 in the case of a nonexempt foundation described in section 4947(a)(2)), which contains questions with respect to such taxes, the filing of such form by such foundation shall constitute the filing of a return with respect to any such act, even though the foundation incorrectly answered such questions.
(b) Failure of private foundation plan, trust, or other organization to file. The period of limitations on assessment and collection described in section 6501 does not begin with respect to any person liable for tax under chapter 42 (other than section 4940) or section 4975 arising from a given act, where the private foundation, plan, trust, or other organization (as the case may be) has not filed its required return that reports such act for the year in which the act (or failure to act) giving rise to liability for such tax occurred.
(c) Example. The provision of this section may be illustrated by the following example: