A CUSIP is a nine-character alphanumeric code that uniquely identifies a North American security (a specific stock or bond issue). The first six characters identify the issuer, the next two the issue, and the last is a check digit.
CUSIP (Committee on Uniform Securities Identification Procedures) is the dominant security identifier in U.S. markets and the key field in a 13F filing, which lists holdings by CUSIP, not ticker. The six-character issuer base is shared across all of an issuer's securities; the two-character suffix distinguishes each issue (common stock, a particular bond, a class of shares).
Mapping CUSIP → ticker → company is deceptively hard at scale: CUSIPs are reassigned, change on corporate actions, and the official mapping is a licensed commercial dataset. This identifier-resolution labor is precisely the "trapped" part of 13F data.
Apple Inc. common stock carries CUSIP 037833100 — the 037833 base is Apple, 10 is the common-stock issue, and 0 is the check digit.
Clean CUSIP→entity resolution is the moat under our 13F data — it is what lets you ask "who holds AAPL" instead of decoding nine-character codes yourself.
Arkolith turns this into live, sourced data your agent can query — SEC filings, insider activity, and market data behind one key, every datapoint traceable to its origin.