Knowledge Base

The International Securities Identification Number (ISIN) is a 12-character alphanumeric code that uniquely identifies a specific security internationally. ISINs are used worldwide to identify financial instruments including equities, bonds, options, derivatives, and futures.

Structure

An ISIN consists of three parts:

• Country Code (2 characters): The ISO 3166-1 alpha-2 country code of the issuing country. For example, 'US' for United States, 'DE' for Germany, 'GB' for United Kingdom.
• National Security Identifier (9 characters): This is typically the national security identifier (like CUSIP for US securities or WKN for German securities) padded with zeros if necessary.
• Check Digit (1 character): A digit calculated using the Luhn algorithm to validate the code.

Examples

The Wertpapierkennnummer (WKN) is a 6-character alphanumeric identifier used primarily in Germany to identify securities. It was the standard identifier in Germany before the introduction of the ISIN.

Structure

A WKN consists of 6 alphanumeric characters. Unlike ISINs or CUSIPs, WKNs do not have a specific structure or check digit. They can contain both letters and numbers.

Examples

Conversion to ISIN

To convert a WKN to an ISIN for a German security:

1. Start with the country code "DE"
2. Add "000" as padding
3. Add the 6-character WKN
4. Calculate the check digit using the Luhn algorithm

Example: WKN 766403 → ISIN DE0007664039

The CUSIP is a 9-character alphanumeric identifier used primarily in the United States and Canada to identify securities. It was developed by the American Bankers Association and is operated by S&P Global Market Intelligence.

Structure

A CUSIP consists of three parts:

• Issuer Code (6 characters): Identifies the issuer of the security
• Issue Number (2 characters): Identifies the specific issue
• Check Digit (1 character): A digit calculated using a modulus 10 algorithm

Examples

The SEDOL is a 7-character alphanumeric identifier used primarily in the United Kingdom and Ireland to identify securities. It is owned and operated by the London Stock Exchange.

Structure

A SEDOL consists of two parts:

• Security Identifier (6 characters): Alphanumeric characters that identify the security
• Check Digit (1 character): A digit calculated using a weighted sum algorithm

Examples

The VALOR is a numeric identifier used primarily in Switzerland to identify securities. It is assigned by SIX Financial Information, a subsidiary of the SIX Group which operates the Swiss Stock Exchange.

Structure

A VALOR is a numeric identifier that can vary in length but is typically 6-9 digits. Unlike other identifiers, it does not have a specific structure or check digit.

Examples

The Financial Instrument Global Identifier (FIGI) is a 12-character alphanumeric identifier used to identify financial instruments globally. It was developed by Bloomberg and is now administered by the Object Management Group (OMG).

Structure

A FIGI is a 12-character alphanumeric code that follows a specific format:

• First character: Exchange or market code
• Next 10 characters: Instrument identification code
• Last character: Check digit

FIGIs are assigned at different levels - composite (for the security across all venues), share class, and instrument (market-specific listing).

Examples

The Legal Entity Identifier (LEI) is a 20-character alphanumeric code that uniquely identifies legal entities participating in financial transactions. It was developed in response to the 2008 financial crisis to improve risk management and assessment.

Structure

An LEI consists of four parts:

• First 4 characters: Prefix identifying the Local Operating Unit (LOU) that issued the LEI
• Next 2 characters: Reserved characters (currently set to "00")
• Next 12 characters: Entity-specific code assigned by the LOU
• Last 2 characters: Check digits

Examples

In addition to the major identifiers covered above, there are several other financial identifier systems used for various purposes:

CINS (CUSIP International Numbering System)

CINS is an extension of the CUSIP system for non-North American securities. It follows the same format as CUSIP but uses a letter for the first character to indicate the country.

CEI (CUSIP Entity Identifier)

The CUSIP Entity Identifier is a 9-character code used to identify legal entities, similar to LEI but within the CUSIP system.

CIK (Central Index Key)

The Central Index Key is a unique identifier assigned by the U.S. Securities and Exchange Commission (SEC) to entities that file disclosures with the SEC through the EDGAR system.

MIC (Market Identifier Code)

The Market Identifier Code is a 4-character code used to identify exchanges, trading platforms, and regulated markets as defined in ISO 10383.

Classification Systems

• CIF (Classification of Financial Instruments): A European classification system for financial instruments
• SIC (Standard Industrial Classification): A system for classifying industries by a four-digit code
• NAICS (North American Industry Classification System): A system that replaced SIC for classifying businesses in North America
• GICS (Global Industry Classification Standard): An industry taxonomy developed by MSCI and S&P for use by the global financial community

Related Organizations

• ANNA (Association of National Numbering Agencies): The organization responsible for coordinating the assignment of ISINs globally
• EDGAR (Electronic Data Gathering, Analysis, and Retrieval): The SEC system that performs automated collection, validation, indexing, and forwarding of submissions by companies and others who are required by law to file forms with the SEC

Converting between different financial identifiers often involves using ISIN as an intermediate step. Here's a summary of the conversion processes:

Direct Conversions

Conversion Complexity

While the conversion rules above cover standard cases, there are exceptions and edge cases that make conversions more complex:

• Non-standard formats: Some ISINs don't follow the standard pattern (e.g., some German ISINs don't use "000" as padding)
• Check digit validation issues: The Luhn algorithm implementation for ISIN check digits can be tricky
• Special characters: Some WKNs contain letters (e.g., BASF11, BAY001) which require special handling

Reference Database

To ensure accuracy, our translator maintains a reference database of verified ISIN-WKN pairs for common securities. When converting between these identifiers, we first check if the security is in our database to ensure correct conversion.

Database entries include major securities such as:

When a security is found in our reference database, the conversion is performed using the verified data, ensuring accuracy even when the standard conversion rules might produce incorrect results.

Financial identifiers often include check digits to validate the code and prevent errors. Here are the algorithms used for different identifiers:

Luhn Algorithm (ISIN)

The Luhn algorithm, also known as the "modulus 10" algorithm, is used to calculate the check digit for ISINs:

1. Convert letters to numbers (A=10, B=11, ..., Z=35)
2. Starting from the rightmost digit (excluding the check digit), double the value of every second digit
3. If doubling results in a two-digit number, add those digits together
4. Sum all the digits
5. The check digit is (10 - (sum % 10)) % 10