| module drop | date | contents |
| 1 | 1999-09-15 | property feature space; activity and state space; product activity and state space parameterisation |
| 2 | 1999-09-29 | property; property space; property distribution; possession of property |
| 3 | 1999-10-19 | product specification or set; activity; state |
| 4 | 2000-01-21 | intepretation complete for activity, state, possession of property, property, property space, property distribution, property identification, product activity and state space parameterisation, and distribution mapping |
| 5 | 2000-03-14 | interpretation of the modules for property updated to be
consistent with the proposal for a part 5x that was agreed in the Melbourne
meeting of TC184/SC4/WG12. This new resource part will link part 50 to the rest
of STEP. A property dictionary for structural analysis has been added, which is derived from part 104 (FEA) |
| 6 | 2000-04-19 | mesh modules revised, and are now integrated with part 42 topology |
| 7 | 2000-07-13 | modules for parameterisation, distribution mapping and property identification have been re-interpreted on to the draft part 5x agreed at the Bordeaux STEP meeting |
| 8 | 2000-09-05 | maths space, maths function and maths value modules have been completed and interpreted on to ISO/DIS 10303-50 |