ISIN
A 12-character alphanumeric code that uniquely identifies securities in international markets, standardizing cross-border trading.
What is ISIN?
An ISIN (International Securities Identification Number) is a 12-character alphanumeric code that uniquely identifies a specific security globally, enabling standardized cross-border trading and settlement. The structure consists of: a 2-character country code (e.g., US for United States, GB for United Kingdom), a 9-character national securities identifier (for U.S. securities, this is the CUSIP), and a single check digit. ISINs are issued by national numbering agencies and used by global exchanges, depositories, and regulatory bodies. The ISO 6166 standard governs ISINs, which are maintained by the Association of National Numbering Agencies (ANNA).
Example
Apple Inc. common stock has the ISIN US0378331005. Breaking it down: 'US' is the country code, '037833100' is the CUSIP, and '5' is the check digit. When a European investor buys Apple shares through a European exchange or via global depositories, the ISIN ensures that both the buyer and seller and their respective clearing systems are referring to exactly the same security.