By Debbie Franklin, Director of Tax and property tax specialist HMRC has adjusted what has been referred to as 'incorrect guidance online' which may mean some property investors and developers are owed considerable sums in stamp duty refunds. The guidance relates to the 3% stamp duty surcharge introduced in 2016 on the acquisition of second homes or residential properties purchased for investment purposes. In the guidance, HMRC asserted that this also applied to Multiple Dwellings Relief claims, even if they were not wholly residential. As a result, those who have paid 3% stamp duty surcharge on a mixed-use multiple dwellings relief claim since 2016 will be entitled to a refund. The surcharge should in fact, only apply where the transaction consisted wholly of residential properties. HMRC has just this week amended its online guidance to reflect this correction. As a consequence, many developers and investors may have overpaid on stamp duty by 200%, and could be owed refunds worth several hundreds of thousands of pounds.