The authorised capital of a company (sometimes referred to as the authorised share capital, registered capital or nominal capital, particularly in the United States) is the maximum amount of share capital that the company is authorised by its constitutional documents to issue (allocate) to shareholders. Part of the authorised capital can (and frequently does) remain unissued. This number can be changed by shareholders' approval. The part of the authorised capital which has been issued to shareholders is referred to as the issued share capital of the company.