Tell me what is an ISIN!
ISIN stands for International Securities Identification Number
As its name suggests, it is a code that uniquely identifies a security across the world, ensuring people from different countries are referring to the same security.
Exxon Mobil is usually known to US investors through its ticker code XOM
, and most probably not know at all through its ISIN US30231G1022
I want to know more!
An ISIN is an alphanumeric code made of 12 digits, following a format described in the ISO 6166
This format is the following:
- 2 alphabetic characters corresponding to an ISO 3166-1 alpha-2 country code.
This country is usually the security issuing country, but the logic is a little more complicated than that...
- 9 alphanumeric characters corresponding to the NSIN (National Securities Identifying Number) of the security.
An NSIN is a code issued by an NNA (National Numbering Agency) - organization in charge of registering all securities in a given geographical area - as part of the ISIN code issuance process.
If the NSIN issued by the NNA is less than 9 characters long, it is extended to an NSIN of 9 characters long by adding leading zeroes.
You can find more information about NSINs on What is a NSIN?.
- 1 numeric character corresponding to the result of a computation made on the first eleven ISIN characters.
This is a control character.
This format can be summarized in the table:
||ISO 3166-1 alpha-2 country code, 2 characters (alphabetic)
||3, 4, 5, 6, 7, 8, 9, 10, 11
||NSIN, 9 characters (alphanumeric)
||Control digit, 1 character (numeric)
For Exxon Mobil of ISIN US30231G1022
, the issuing country is US
(United States), the NSIN (known as CUSIP
) is 30231G102
and the control character is 2
What if I want to know even more?
I can tell you one more thing:
- An ISO 3166-1 alpha-2 country code does not always correspond to a "real" country.
For example, there are ISINs starting with XS, but XS does not correspond to any country in the world (only exception allowed by ISO 6166)!
Those XS-starting ISINs are associated to debt securities most of the time (but not always) directly deposited in an ICSD (International Central Securities Depositories) like Euroclear, Clearstream, and issued by those ICSD.
I can also give you a link to the complete ISO 6166 norm
, hosted on my site.
And if you still want more details about ISINs, you can start your journey on the Wikipedia ISIN page
, and then continue on the ANNA site
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