A stock-transfer form is the paper instrument by which shares are transferred from one person to another. If no chargeable consideration is given, the transfer is exempt from stamp duty, the form does not need to be stamped or sent to HMRC.
Where a company purchases its own shares, the shares are delivered to the company and surrendered without the need for a stock-transfer form. The company must file a return on Form SH03 and file this with the Registrar of Companies. It is this form that is treated as if it were an instrument transferring the shares on sale to the company (see further ¶400-260).