Stamp Duty Reserve Tax is a UK tax that may be payable depending on the type of transfer. As a general rule, if no money is changing hands then the transaction is not liable for Stamp Duty. For example, if you are giving your shares to another person as a gift, the transfer will fall into category 'L'.
More information about Stamp Duty and Stamp Duty Reserve Tax is available on the HM Revenue & Customs website. For example, more details of exemptions are detailed in chapter 2 of the Stamp Office Manual
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