| A | agency single order |
| B | short exempt transaction b |
| C | program order nonindex arb for member firmorg |
| D | program order index arb for member firmorg |
| E | registered equity market maker trades |
| F | short exempt transaction f |
| H | short exempt transaction h |
| J | program order index arb for individual customer |
| K | program order nonindex arb for individual customer |
| L | short exempt affiliated |
| M | program order index arb for other member |
| N | program order nonindex arb for other member |
| O | competing dealer trades o |
| P | principal |
| R | competing dealer trades r |
| S | specialist trades |
| T | competing dealer trades t |
| U | program order index arb for other agency |
| W | all other orders as agent for other member |
| X | short exempt not affiliated |
| Y | program order nonindex arb for other agency |
| Z | short exempt nonmember |