The Free On-line Dictionary of Computing (30 December 2018):

ANSI X12

    Standards defining the structure, format, and
   content of business transactions conducted through Electronic
   Data Interchange (EDI).  ANSI X12 is produced by the
   committee ASC X12, supported by the Data Interchange
   Standards Association, Inc. (DISA).

   [(http://onlinewbc.org/Docs/procure/standard.html)].

   (1999-09-18)