A best fit lookup between Lower Layer Super Output Areas (LSOA) as at December 2011 and local enterprise partnerships (LEP) as at December 2014 in England (File Size 2.2MB).
For more information and an overview of best-fitting follow this link - https://geoportal.statistics.gov.uk/datasets/f0aac7ccbfd04cda9eb03e353c613faa/about
REST URL of Feature Access Service – https://services1.arcgis.com/ESMARspQHYMw9BZ9/arcgis/rest/services/LSOA11_LEP14_EN_LU_V2_d646b55d8d6744e7a5d48ece8f5e6f06/FeatureServer