If at any time after the preparation of listing particulars which have been submitted to the FCA under section 79 and before the commencement of dealings in the securities concerned following their admission to the official list—
the issuer must, in accordance with listing rules, submit supplementary listing particulars of the change or new matter to the FCA, for its approval and, if they are approved, publish them.
"Significant" means significant for the purpose of making an informed assessment of the kind mentioned in section 80(1).
If the issuer of the securities is not aware of the change or new matter in question, he is not under a duty to comply with subsection (1) unless he is notified of the change or new matter by a person responsible for the listing particulars.
But it is the duty of any person responsible for those particulars who is aware of such a change or new matter to give notice of it to the issuer.
Subsection (1) applies also as respects matters contained in any supplementary listing particulars previously published under this section in respect of the securities in question.