Speed Read: This article HMRC's answers to a question concerning SDLT on the grant of options which are combined with other transactions in circumstances which may give rise, either on the grant or exercise of the option, to an exchange. When advising on this topic, it is vital to recognise transactions where the SDLT liability is determined by reference to the market value of the chargeable interest acquired, particularly if this applies on the exercise of an option which may occur years after the option is granted, and especially if the exercise is dependent on an event, such as the grant of planning permission, which could have a profound effect on the value of the interest acquired.