(1) Authorisation under this Part is not needed for a donation except to the extent that the total amount of -
(b) other relevant donations made in the period of 12 months ending with the date on which that donation is made,
exceeds £5,000.
(2) In this section -
"donation" means a donation to a political party or other political organisation or to an independent election candidate; and
"other relevant donations" means -
(a) in relation to a donation made by a company that is not a subsidiary, any other donations made by that company or by any of its subsidiaries;
(b) in relation to a donation made by a company that is a subsidiary, any other donations made by that company, by any holding company of that company or by any other subsidiary of any such holding company.
(3) If or to the extent that a donation is exempt by virtue of this section from the requirement of authorisation under this Part, it shall be disregarded in determining what donations are authorised
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