FIX

The FIX protocol comes with a wide set of standards. In practice, most trading venues and market participants will only inherit or implement a subset of these standards.

To distinguish between one FIX-based protocol from another, one may refer to them as a different dialects of FIX.

Many venues also have their own proprietary wire protocols that draw inspiration from FIX, but do not conform enough to FIX to be called a FIX or FIX-based protocol. Some signs of this include the use of the term "security", commonly found on FIX message and field definitions, for derivative instruments which are not securities.