13(1)Sub-paragraph (3) below applies where—
(a)under section 239(1), advance corporation tax has been set against the subsidiary’s liability to corporation tax for an accounting period (“the relevant accounting period”),
(b)the advance corporation tax is, includes or is part of advance corporation tax which is treated as paid by the subsidiary in respect of that period on the assumption that section 240(2) required that treatment, and
(c)after an assessment to corporation tax for that period has become final, the subsidiary becomes aware of facts (“the true facts”) which, by virtue of section 240(1B), make that treatment incorrect.
(2)Sub-paragraph (3) below also applies where—
(a)by virtue of section 239(4), advance corporation tax has been set against the subsidiary’s liability to corporation tax for an accounting period (“the relevant accounting period”),
(b)the advance corporation tax is, includes or is part of advance corporation tax which is treated as paid by the subsidiary in respect of a previous accounting period on the assumption that section 240(2) required that treatment, and
(c)after an assessment to corporation tax for that period has become final, the subsidiary becomes aware of facts (“the true facts”) which, by virtue of section 240(1B), make that treatment incorrect.
(3)The subsidiary must, before the end of the period of three months beginning with the day on which it becomes aware of the true facts, provide an officer of the Board with an assessment (a self-assessment) of the amount of corporation tax which was due for the relevant accounting period on the basis of the true facts.
(4)The tax shall be treated as due and payable, in accordance with section 59D of the Management Act, on the day following the expiry of nine months from the end of the relevant accounting period of the subsidiary.
(5)The standard provisions about enquiries into self-assessments (given by paragraph 14 below) apply to self-assessments provided under this paragraph.
(6)For the purposes of this paragraph it shall be assumed that advance corporation tax actually paid (or correctly treated as paid) by the subsidiary has been set against the subsidiary’s liability to corporation tax before any advance corporation tax incorrectly treated as paid by the subsidiary.