641. Authority for market purchase
(1) A company may only make a market purchase of its own shares if the purchase has first been authorised by a resolution of the company.
(2) That authority—
(a) may be general or limited to the purchase of shares of a particular class or description, and
(b) may be unconditional or subject to conditions.
(3) The authority must—
(a) specify the maximum number of shares authorised to be acquired, and
(b) determine both the maximum and minimum prices that may be paid for the shares.
(4) The authority may be varied, revoked or from time to time renewed by a resolution of the company.
(5) A resolution conferring, varying or renewing authority must specify a date on which it is to expire, which must not be later than five years after the date on which the resolution is passed.
(6) A company may make a purchase of its own shares after the expiry of the time limit specified if—
(a) the contract of purchase was concluded before the authority expired, and
(b) the terms of the authority permitted the company to make a contract of purchase that would or might be executed wholly or partly after its expiration.
(7) A resolution to confer or vary authority under this section may determine either or both the maximum and minimum price for purchase by—
(a) specifying a particular sum, or
(b) providing a basis or formula for calculating the amount of the price (but without reference to any person's discretion or opinion).
(8) Chapter 3 of Part 3 (resolutions affecting a company's constitution) applies to a resolution under this section.