Industry classification or industry taxonomy organizes companies into industrial groupings based on similar production processes, similar products, or similar behavior in financial markets.

A wide variety of taxonomies is in use, sponsored by different organizations and based on different criteria.

Abbreviation	Full name	Sponsor	Criterion/ Unit	Node count by level	Issued
ISIC	International Standard Industrial Classification of All Economic Activities	United Nations Statistics Division	production/ establishment	4 digits 21/88/238/419	1948–present (Rev. 4, 2008)
NAICS	North American Industry Classification System	Statistical bureaus of US, Canada, and Mexico	production/ establishment	6 digits 17/99/313/724/1175 (/19745)1	1997, 2002, (2012)
NACE	Statistical Classification of Economic Activities in the European Community Statistical classification of economic activities in the European Community The Statistical Classification of Economic Activities in the European Community , commonly referred to as NACE, is a European industry standard classification system consisting of a 6 digit code.NACE is similar in function to the SIC and NAICS systems:*Standard Industrial...	European Community	production/ establishment	6 digits
ANZSIC	Australian and New Zealand Standard Industrial Classification
SIC	Standard Industrial Classification Standard Industrial Classification The Standard Industrial Classification is a United States government system for classifying industries by a four-digit code. Established in 1937, it is being supplanted by the six-digit North American Industry Classification System , which was released in 1997; however certain government...	US	production/ establishment	4 digits 1004 categories	1937–1987 (superseded by NAICS, but still used in some applications)
ICB	Industry Classification Benchmark Industry Classification Benchmark The Industry Classification Benchmark is an industry classification taxonomy developed by Dow Jones and FTSE. It is used to segregate markets into sectors within the macroeconomy...	FTSE FTSE FTSE may refer to:* The FTSE Group* Stock market indices published by the FTSE Group, particularly the FTSE 100 Index on the London Stock Exchange* The Fundamental theorem of software engineering...	market/ company	10/20/41/114
GICS	Global Industry Classification Standard Global Industry Classification Standard The Global Industry Classification Standard is an industry taxonomy developed by MSCI and Standard & Poor's for use by the global financial community. The GICS structure consists of 10 sectors, 24 industry groups, 68 industries and 154 sub-industries into which S&P has categorized all major...	Standard & Poor's Standard & Poor's Standard & Poor's is a United States-based financial services company. It is a division of The McGraw-Hill Companies that publishes financial research and analysis on stocks and bonds. It is well known for its stock-market indices, the US-based S&P 500, the Australian S&P/ASX 200, the Canadian... , Morgan Stanley Capital International Morgan Stanley Capital International MSCI Inc. is a provider of investment decision support tools to investment institutions. Products include indices, portfolio risk and performance analytics - for use in managing equity, fixed income and multi-asset class portfolios - and governance tools....	market/ company	2-8 digits 10/24/68/154
TRBC	Thomson Reuters Business Classification Thomson Reuters Business Classification The Thomson Reuters Business Classification is an industry classification of global companies; it is owned and operated by Thomson Reuters and is also the basis for Thomson Reuters Indices.-Coverage:...	Thomson Reuters Thomson Reuters Thomson Reuters Corporation is a provider of information for the world's businesses and professionals and is created by the Thomson Corporation's purchase of Reuters Group on 17 April 2008. Thomson Reuters is headquartered at 3 Times Square, New York City, USA...	market/ company	10/25/52/124

¹The NAICS Index File lists 19745 rubrics beyond the 6 digits which are not assigned codes.

Besides the widely-used taxonomies above, there are also more specialized proprietary systems:

• Revere Data, line-of-business, about 11,000 leaf nodes
• IndustryBuildingBlocks, line-of-business about 12,000 leaf nodes
• First Research taxonomy, used by Hoover's
  Hoover's
  Hoover's, Inc., a subsidiary of Dun & Bradstreet, is a business research company that has provided information on U.S. and foreign companies and industries since 1990. Since 1993, the company has made its information available on its website.-Operations:...
  
  
• WAND, Inc.'s Product and Service Taxonomy