Volume 1 of the FIX 5.0 Service Pack 2 (with 20110818 Errata) contains the FIX tag-value syntax rules and the FIXML Schema syntax rules in the “FIX Protocol Syntax” section – FIX Tag=Value Syntax and FIXML Syntax.
Tag: FIXML Spec
Package
FIXML Schema – Latest EP
FIXML Schema package for the latest published FIX 5.0 SP2 Extension Pack: EP266