What is the difference between Custody and Sub Custody?

Custody : A custodian bank, or simply custodian, is a specialized financial institution responsible for safeguarding a firm's or individual's financial assets and is not engaged in "traditional" commercial or consumer/retail banking such as mortgage or personal lending, branch banking, personal accounts, automated teller machines (ATMs) and so forth.

Sub-Custody : An institution providing custody services, with respect to securities traded in a particular market or jursidiction, on behalf of another custodian (e.g. a global custodian) who may not have an operation in that jurisdiction.

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