| AA | Aluminum Association |
| AB | Assigned by Buyer |
| AI | Automotive Industry Action Group |
| AP | American Petroleum Institute |
| AS | Assigned by Seller |
| AX | ANSI Accredited Standards Committee, X12. |
| BI | Book Industry Systems Advisory Committee |
| CA | Chemical Abstract Services (CAS) |
| CB | Copper and Brass Fabricators Council, Inc. |
| CC | National Cotton Council of America |
| CI | Chemical Industry Data Exchange (CIDX) |
| CM | Carbide Manufacturers |
| CR | Commander - Rome Air Development Center |
| DD | Department of Defense |
| DE | Drug Enforcement Administration |
| DR | National Wholesale Druggists Association |
| EI | Electronic Industries Association |
| EU | Electric Utilities |
| FA | Fabric and Supplier Linkage Council (FASLINC) |
| FD | Uniform Code Council (UCS) |
| GC | Graphics Communications Association |
| GU | Natural Gas Utilities |
| IS | International Standards Organization |
| MS | Military Standard |
| NE | EDX |
| NR | National Retail Merchants Association |
| OP | Office Products |
| PA | American Paper Institute |
| PI | Petroleum Industry |
| ST | American Iron & Steel Institute |
| TD | Transportation Data Coordinating Committee: Electronic Data Interchange Association (TDCC:EDIA) |
| TI | Telecommunications Industry |
| TM | American Textile Manufacturers Institute |
| TX | American Apparel Manufacturers Association |
| VI | Voluntary Interindustry Communication Standards (VICS) |
| ZZ | Mutually Defined |