Variation of shareholder rights requires class consent or a separate special resolution, subject to company constitution and issue terms. Variation of rights attached to a class of shares may be effected by the consent in writing of the requisite proportion of holders of that class or by the sanction of a special resolution passed at a separate meeting of the holders of that class, provided such variation is authorized by the memorandum or articles or, in their absence, is not prohibited by the terms of issue of those shares.