571. Variation of class rights: companies having a share capital
(1) This section is concerned with the variation of the rights attached to a class of shares in a company having a share capital.
(2) Rights attached to a class of a company's shares may only be varied—
(a) in accordance with provision in the company's articles for the variation of those rights, or
(b) where the company's articles contain no such provision, if the holders of shares of that class consent to the variation in accordance with this section.
(3) This is without prejudice to any other restrictions on the variation of the rights.
(4) The consent required for the purposes of this section on the part of the holders of a class of a company's shares is—
(a) consent in writing from the holders of at least three-quarters of the issued shares of that class (excluding any shares held as treasury shares), or
(b) a special resolution passed at a separate general meeting of the holders of that class sanctioning the variation.
(5) Any amendment of a provision contained in a company's articles for the variation of the rights attached to a class of shares, or the insertion of any such provision into the articles, is itself to be treated as a variation of those rights.
(6) In this section, and (except where the context otherwise requires) in any provision in a company's articles for the variation of the rights attached to a class of shares, references to the variation of those rights include references to their abrogation.