How Does a Block Trade Differ from an ‘All-or-None’ Order Type?

An 'all-or-none' (AON) order is a type of limit order placed on a public exchange that must be executed in its entirety or not at all, preventing partial fills. A block trade, conversely, is a large, privately negotiated transaction executed off-exchange via an OTC desk.

While both aim for full execution, the AON order is a visible exchange mechanism, whereas the block trade is a private, non-transparent execution method.