Direct market access

Direct market access (DMA) is a term used in financial markets to describe electronic trading facilities that give investors wishing to trade in financial instruments a way to interact with the order book of an exchange. Normally, trading on the order book is restricted to broker-dealers and market making firms that are members of the exchange. Using DMA, investment companies (also known as buy side firms) and other private traders utilize the information technology infrastructure of sell side firms such as investment banks and the market access that those firms have, but control the way a trading transaction is managed themselves rather than passing the order over to the broker's own in-house traders for execution. Today, DMA is often combined with algorithmic trading giving access to many different trading strategies. Certain forms of DMA, most notably "sponsored access," have raised substantial regulatory concerns because of the potential for a malfunction by an investor to cause widespread market disruption.

As financial markets moved on from traditional open outcry trading on exchange trading floors towards decentralised electronic, screen-based trading and information technology improved, the opportunity for investors and other buy side traders to trade for themselves rather than handing orders over to brokers for execution began to emerge. The implementation of the gave market participants the ability to route orders electronically to execution desks. Advances in the technology enabled more detailed instructions to be submitted electronically with the underlying order.

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