Omnibus Customer Securities Accounts

An Omnibus Customer Securities Account is a securities account used by a brokerage firm or its affiliated clearing firm in order to maintain appropriate custody of underlying securities for the purpose of satisfying the custody obligations of the broker-dealer towards its customers. Article 8 of the US Uniform Commercial Code provides for a standard settlement procedure for securities transfers to be effected by book entry when the underlying securities are registered in the name of the designated nominee of a securities intermediary.

Source: Wikipedia — Omnibus Customer Securities Accounts (CC BY-SA 4.0)