Part 4.1 ANSI X12 - Introduction

What does 12 represent in X12?
The number 12 represents a subcommittee of twelve.

ANSI ASC X12 - Header and trailer
This standard has 3 envelopes.  Transaction Set Envelope is inside the Functional Group Envelope, and the Functional Group Envelope is inside the Interchange Control Envelope. All the three envelopes are mandatory.

ISA ----------------------------------------    +     (Interchange Control Header)
                   GS -----------------------    +    |     (Functional Group Header)
                                        ST ----    +    |    |     (Transaction Set Header)
                                                      |      |    |
                                        SE ----    +    |    |     (Transaction Set Trailer)
                    GE ----------------------    +    |     (Functional Group Trailer)
IEA ----------------------------------------    +     (Interchange Control Trailer)

ANSI X12 - Envlope information
ISA -----------------------------------------    +     (Organization Level Information)
                GS --------------    ---------    +    |     (Department Level Information)
                                         ST ----    +    |    |    (Types of Transaction Set)
                                                       |      |    |
                                         SE ----    +    |    |     (Types of Transaction Set)
        GE --------------------------------    +    |    (Department Level Information)
IEA -----------------------------------------    +     (Organization Level Information)

Note -

• Interchange Control Envelope has the information at an organization level.
• Functional Group Envelope has the information at a department level.
• Transaction Set Envelope has the type of transaction set to be sent to departments.
• If there is no information about the department level, then the organization level information will use as a department level information.
• For Example - Controller ID

ANSI ASC X12 Subcommittees

X12A - Education Administration
X12C - Communications and Control
X12E - Product Data
X12F - Finance
X12G - Government
X12H - Materials Management
X12I - Transportation
X12J - Technical Assessment
X12K - Purchasing
X12L - Industry Standards Transition
X12M - Distribution and Warehousing