632. Authority for purchase of own shares
(1) A limited company may only purchase its own shares-
(a) by an off-market purchase, authorised in accordance with section 633 or in pursuance of a contract approved in advance in accordance with section 634,
(b) by a market purchase, authorised in accordance with section 641.
(2) A purchase is “off-market” if the shares either-
(a) are purchased otherwise than on a recognised investment exchange, or
(b) are purchased on a recognised investment exchange but are not subject to a marketing arrangement on the exchange.
(3) For this purpose a company’s shares are subject to a marketing arrangement on a recognised investment exchange if the company has been afforded facilities for dealings in the shares to take place on the exchange-
(i) without prior permission for individual transactions from the authority governing that investment exchange, and
(ii) without limit as to the time during which those facilities are to be available.
(4) A purchase is a “market purchase” if it is made on a recognised investment exchange and is not an off-market purchase by virtue of subsection 632(2)(b).
(5) In this section ”recognised investment exchange” means an investment exchange so determined in rules made by the Board.