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MEMORANDUM 

To: Docket EPA-HQ-OAR-2009-0925 

From: Lisa Grogan-McCulloch, EPA/Climate Change Division and 

 Ruth Mead and Amanda Baynham, ERG 

Date: March 2, 2010 

Subject: Summary of Existing Company Identifier Systems 

INTRODUCTION 

EPA has identified several government and commercial data systems that assign unique numeric 

or alphanumeric identifiers to individual businesses for the purpose of storing and retrieving data 

on corporate structure and ownership, and North American Industry Classification System 

(NAICS) codes. These data systems included: Dun & Bradstreet Data Universal Numbering 

System (DUNS), Securities and Exchange Commission (SEC) Central Index Key, Stock Tickers, 

Committee on Uniform Security Identification Procedures (CUSIP), International Securities 

Identification Number (ISIN), Federal Employee Identification Numbers (FEIN), National 

Institutes of Health (NIH) Electronic Research Administration, and LexisNexis. This 

memorandum provides a brief description of each data system. 

Dun & Bradstreet Data Universal Numbering System (DUNS)

The Data Universal Numbering System (DUNS) was developed in the 1960s by Dun & 

Bradstreet to support their credit reporting business. DUNS tracks each individual business entity 

by assigning each business location a unique 9-digit numerical identifier (referred to as a DUNS 

number). The DUNS number is used to identify individual business entities in databases 

maintained by Dun & Bradstreet that contain financial and other company data (including 

Standard Industrial Classification (SIC) and NAICS codes). Dun & Bradstreet provides limited 

use of this data to individuals, businesses, organizations, and governments for a fee. The data is 

collected from a variety of sources, including telephone interviews, company financial 

documents, court and legal filings, business registries, government records, and publications. 

DUNS numbers are widely used today both nationally and internationally by governments, 

industry, and other organizations. The database currently contains more than 29 million entities 

in the United States and 150 million entities worldwide. To be included in the database, 

businesses must apply for a DUNS number. There are no restrictions of the type of entities that 

can be assigned a DUNS number. For example, DUNS numbers are assigned to both public and 

private entities, non-profit organizations, or small family owned businesses. 1 

Dun & Bradstreet also uses the DUNS numbers to track corporate family structures by linking 

DUNS numbers for each entity to its parents, subsidiaries, headquarters, and branches. Using 

 

1

 Dun & Bradstreet: DUNS Number, http://www.dnbgov.com/data_duns.html, accessed March 1, 2010. 
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this system, Dun & Bradstreet assembles corporate family trees, which identify the highest-level 

parent company both at the country level and globally. DUNS numbers are linked only when 

one business location has a financial and legal responsibility for another location. Legal and 

financial responsibility is established only when one entity owns more than 50% of the other 

(e.g., a parent company owns 60% of a subsidiary). Consequently, Dun & Bradstreet’s corporate 

trees do not include business relationships where one corporation owns only a minority interest 

in another or where ownership is split between two or more companies). 2

Securities and Exchange Commission (SEC) Central Index Key

The Securities and Exchange Commission (SEC) issues a Central Index Key (CIK) number to 

business entities required to file quarterly and annual financial statements with the SEC. The 

CIK is a 10-digit number and is used to identify the filings of a company, person, or entity in 

several online databases, such as the Electronic Data-Gathering, Analysis, and Retrieval 

(EDGAR) system. Since CIKs are issued only to business entities required to file disclosures 

with the SEC, privately held companies do not have CIK numbers.3

Stock Symbols

Stock symbols (sometimes called stock ticker symbols) were developed by Standard & Poor’s 

and are unique identifiers assigned to each security traded on U.S. financial exchanges. For 

example, stock symbols are assigned to publicly traded shares of a company’s stock traded on an 

exchange. While stock tickers are specific to a corporation listed on an exchange, they are not 

unique to the company, as the same company may have different stock tickers on different 

exchanges or different tranches of stock listed on the same exchange. The stock symbols consist 

of one to five letters and may have additional suffixes or letters to differentiate between different 

types of stock (e.g., preferred and common stock). Only publicly traded companies have stock 

ticker symbols. 

Committee on Uniform Security Identification Procedures (CUSIP)

The Committee on Uniform Security Identification Procedures (CUSIP) Service Bureau assigns 

National Securities Identification Numbers (usually called CUSIPs) to all securities issued in the 

United States and Canada by municipalities, governments, corporations, and other business 

entitities. CUSIPs are nine-character alphanumeric identifiers that are used to facilitate the 

settlement of trades. The first six characters of each CUSIP identify the issuer of the security 

and are referred to as the Issuer Number. The remaining three characters include two characters 

(numerical or alphabetic) used to identify the security and one character used as a check digit. 

CUSIPS are assigned to a wide variety of securities, including common stock, preferred stock, 

corporate bonds, annuities, municipal bonds, derivatives, syndicated loans, and U.S. Treasury 

Notes. Only entities that have issued securities have an assigned six character CUSIP Issuer 

Number. Information on corporate mergers, acquisitions, and name changes is also tracked in 

 

2

 Dunn and Bradstreet: Corporate Linkage, http://www.dnbgov.com/data_corporate.html, accessed March 1, 2010. 

3

 U.S. Securities and Exchange Commission, “Draft EDGAR Filer Manual”, Volume I, Version 8, September 2009 

(http://www.sec.gov/info/edgar/edgarfm-vol1-v8_d.pdf). 
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the CUSIP database. Access to the information in the CUSIP database is restricted and requires 

licensing agreements and fees.4 

International Securities Identification Number (ISIN)

The International Securities Identification Number (ISIN) is a unique twelve character 

alphanumeric identifier issued to securities, such as debt securities, shares, options, derivatives, 

and futures. It is similar to the CUSIP but is used for all types of securities, not just those traded 

in the U.S. and Canada. Unlike stock symbols which vary by stock exchange, the ISIN is unique 

to the security and does not change when the security is traded on a different exchange or other 

trading platform. ISINs must conform to International Standards Organization (ISO) 6166 and 

consist of three parts: (1) a two letter country code; (2) a nine character alphanumeric security 

identifier (called the National Securities Identifying Number (NSIN)); and (3) a check digit. The 

NSIN is assigned by governing bodies in each country. In the U.S., the NSIN is assigned by the 

CUSIP Service Bureau. CUSIPs can be converted to ISINs by adding the country code to the 

beginning of the CUSIP and an additional check digit to the end. As with CUSIPs, ISINs are 

limited to entities that have issued securities.5

 

Federal Employer Identification Numbers (FEIN)

Federal Employer Identification Numbers (FEIN) are unique 9-digit numbers assigned by the 

Internal Revenue Service (IRS) to business entities operating in the United States. The IRS uses 

FEINs to identify taxpayers that are required to file various business tax returns. Business 

entities that have one or more employees are required to obtain a FEIN. FEINs are issued to a 

variety of public and private business entities, including corporations, partnerships, non-profit 

organizations, limited liability companies (LLCs), and government agencies. FEINs are subject 

to IRC section 6103. The regulation states that all information included on a tax return is 

confidential unless the information "does not include data in a form which cannot be associated 

with, or otherwise identify, directly or indirectly, a particular taxpayer." Furthermore, the 

regulation is very specific on the conditions under which taxpayer information may be released 

to employees or officials of the Executive Branch agencies, and EPA’s collection activities are 

not covered under any conditions set forth by the regulation. Therefore, absent a legislative 

change, EPA cannot require FEIN.6 

 

National Institutes of Health, Electronic Research Administration

The National Institutes of Health (NIH) Electronic Research Administration maintains a database 

of grantee organizations that have previously registered with NIH. Each entity listed in the 

database is assigned a unique Institutional Profile File (IPF) number, which is used by the 

National Institutes of Health for tracking grant awards. IPF numbers are assigned only to 

 

4

 CUSIP Global Services, “Inside the CGS Identification System”, 

https://www.cusip.com/cusip/pdf/Inside_CGS_09-12-02.pdf. 

5

 Association of National Numbering Agencies, http://www.anna-web.com/index.php/home/isinsaiso6166, accessed 

March 1, 2010. 

6

 Department of the Treasury, Internal Revenue Service, “Understanding Your Employer Identification Number 

(EIN)”, Publication 1645 (Rev. 12-2009), Catalog Number 14332X, http://www.irs.gov/pub/irs-pdf/p1635.pdf. 
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companies, organizations, or institutions that have or have had grant support from the NIH. The 

database also includes the location and DUNS number for each entity listed in the database. The 

database currently contains approximately 17,500 registered entities.7

LexisNexis

LexisNexis provides a wide range of public records through searchable databases for which users 

pay subscription fees to access and use the data. LexisNexis’ Directory of Corporate Affiliations

database maintains records of corporate ownership. The database covers both U.S. and 

international businesses and contains records for approximately 210,000 public and private 

companies. The data includes information on parent companies, affiliates, subsidiaries, and 

divisions. Each company record includes a unique company identifier number, SIC and NAICS 

codes, company hierarchy (including the highest-level parent company), and other ownership 

information (including percentage of ownership). There is no facility-level data in the database. 

The database maintains data on several different types of company relationships. These include 

subsidiaries where the parent company owns more than 50% of another company, joint ventures 

where two or more companies share ownership, affiliates where the parent company owns less 

than 50% of another company, divisions of a company, branches, factories, and plants. The 

information is collected from publicly available documents (e.g., court records, financial 

disclosure statements, and press releases) and directly from companies. 8

The Directory of Corporate Affiliations focuses primarily on larger companies that have annual 

revenues exceeding $10 million. Information on small businesses is generally not available from 

this source. The directory includes both private and publicly traded business entities and 

includes records for all major publicly traded companies that have U.S. headquarters 

(approximately 6,000 U.S. public parent companies and 40,000 subsidiaries), approximately 

50,000 privately held parent companies, and 26,000 privately held subsidiaries. There is a 

separate sub-directory for international companies (i.e., those whose highest-level parent 

company is located outside the U.S.), which contains records for approximately 16,000 

international parent companies. 9

 

7U.S. Department of Health and Human Services, Electronic Research Administration, 

http://era.nih.gov/commons/index.cfm, accessed March 1, 2010. 

8

 Lexis Nexis: Corporate Affiliations, http://www.corporateaffiliations.com/, accessed March 1, 2010. 

9

 Lexis Nexis: Corporate Affiliations, http://www.corporateaffiliations.com/, accessed March 1, 2010.