CUSIP
Committee on Uniform Securities Identification Procedures
A nine-character alphanumeric identifier assigned to securities in the United States and Canada.
CUSIP numbers are issued by CUSIP Global Services, operated by S&P Global Market Intelligence. The system was developed in 1968 to standardize the identification of securities in North American markets. The nine characters consist of eight alphanumeric characters followed by a check digit. The first six characters identify the issuer, the seventh and eighth identify the specific security type and issue, and the ninth is a mathematical check digit for validation. CUSIPs are mandatory for all securities transactions in the US and are used for clearing, settlement, and regulatory reporting purposes.
Example
037833100 (Apple Inc. common stock) — 037833 (issuer) + 10 (security type) + 0 (check digit)