The Representation of the People (Supply of Information) Regulations 2014
These Regulations require electoral registration officers in Great Britain to supply national and local political parties, for a limited period, with information as to whether entries on an electoral register were either made following an application under the system of individual electoral registration, which begins in 2014, or were included as a result of the entry having been confirmed in accordance with the transitional arrangements for the new system. The information may only be used for the purposes of electoral registration (or of civil or criminal proceedings) and may not be used after 7th May 2015.