Enterprise Standard Industrial Classification

In addition to the SIC, where each plant or establishment receives an individual code, the federal government uses the Enterprise Standard Industrial Classification (ESIC) (2), where each company receives a single code according to the company s dominant activity. In the ESIC system, the real estate transactions of Shell Oil are all classed as ESIC 29 and the chemical operations of firms like General Electric, Borden, and Food Machinery Corporation are not part of ESIC 28. This system is useful in compiling and analyzing financial and related data (e.g., income, expenses, and profits that may be available only on a company basis). The existence of two systems requires care and discrimination in analyzing economic data. 

Enterprise Standard Industrial Classification Manual. Government Printing Office. Washington, DC. 1974. 

---