Companies House does not allow a ‘carbon copy’ of a business name. However, ‘passing off’ is not limited to exact name copying, for example there could be 2 limited businesses registered on Companies House with confusingly similar names ie; ‘Excelsior Roofers Ltd’ and ‘Excelsior Roofing & Maintainace Ltd’. Should these businesses overlap in services and trading region, there would likely be a case of passing off.