gbjbaanb wrote:It always beats me why all the tech companies using stock quotes end up with a magic identifier for stocks, when there's (at least) SEDOL and ISIN already there waiting to be used!
Because then the data provider/tech company has full and proprietary ownership of the identification data point without being beholden to the owners of the "standard" identifiers who may then impose prohibitive terms or costs on the usage of them. Also the ISIN creators may not even have such IDs for all the security types that the company is interested in (private portfolios for example). They can also build all their internal systems in a consistent way to power industry solutions.
By way of example the code that Morningstar assign to this fund (at the end)
https://www.theaic.co.uk/companydata/0P00008ZPP will always be the same number of characters if it is a UK Stock or a Mongolian unlisted fund or Australian LIC etc. Then local identifiers or codes can be sourced/displayed separately depending on the use case.
In simple terms it is essential to have a coding system to create a global database that can service 100 products (terminals/web feeds etc) for 460,000 securities over dozens of structures (Private securities, OE, CEF, Equity, ETF, Fixed Income, S/Ps etc).
Also it allows a security to be set up on a providers database pre-launch. You do not want to be waiting for a code to be announced if a client is expecting to see the rest of the data for the security at 7am on day one.
Probably a few more reasons that database architects far smarter than me could point to!