FIGI and Open Symbology

Every tradeable security needs a unique identifier so systems can reference "this exact instrument" without ambiguity, but the most widely used identifiers historically — CUSIP in the US, ISIN internationally — are licensed products, meaning a data vendor or user often has to pay a fee to use them at scale, even just to store or display them in an internal database. This friction motivated the creation of the FIGI (Financial Instrument Global Identifier), a 12-character alphanumeric code that is free, openly published, and carries no licensing restriction on use or redistribution.

FIGI was created by Bloomberg and later handed to the Object Management Group, an independent standards body, so that it wouldn't remain tied to a single commercial vendor's control. Each FIGI is permanent and specific to one instrument at one level — a share class, a specific listing on a specific exchange, and a composite identifier that groups all listings of the same security together all get distinct FIGIs, which lets systems distinguish "the same company's stock" from "this particular exchange listing of it."

For a quant building any kind of multi-source dataset, the practical benefit is being able to join data from different vendors on a common key without worrying about licensing terms that restrict how a proprietary identifier can be stored, shared, or published. FIGI has become a common mapping key specifically for this reason, even at firms that still use CUSIP or ISIN internally for other purposes.