On 3 December 2014 the Chancellor announced an increase to the R&D incentives for SMEs with the relief increasing from 225% to 230% from 1 April 2015.  Large companies also benefit with an increase in the R&D Expenditure Credit (RDEC) from 10% to 11%.  However, a restriction in the costs that can be claimed was also announced.  Where a company incurs expenditure on materials which are incorporated into prototype products that are sold to customers, it will no longer be possible to make a claim for these materials.  This does provide clarity in an area that has always been uncertain but it will have an impact on the size of claims made by companies in engineering and manufacturing sectors from 1 April 2015.