Financial Information eXchange

The Financial Information eXchange (FIX) protocol is an electronic initiated in 1992 for international real-time exchange of information related to the securities transactions and markets. With trillions of dollars traded annually on the NASDAQ alone, financial service entities are investing heavily in optimizing electronic trading and employing direct market access (DMA) to increase their speed to financial markets. Managing the delivery of trading applications and keeping latency low increasingly requires an understanding of the FIX protocol.

The FIX Protocol specification was originally authored in 1992 by Robert "Bob" Lamoureux and Chris Morstatt to enable electronic communication of equity trading data between Fidelity Investments and Salomon Brothers. FIX initially addressed information between broker-dealers and their institutional clients. At the time, this information was communicated verbally over the telephone. Fidelity realized that information from their broker-dealers could be routed to the wrong trader, or simply lost when the parties hung up their phones. It wanted such communications to be replaced with machine readable data which could then be shared among traders, analyzed, acted on and stored. For example, broker-dealers call with an indication of interest (IOI) to buy or sell a block of stock. The FIX initiative created new messages such as the IOI.

According to the FIX Trading Community, FIX has become the de facto messaging standard for pre-trade and trade communication in the global equity markets, and is expanding into the post-trade space to support straight-through processing, as well as continuing to expand into foreign exchange, fixed income and derivatives markets.

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