BPML Activities Requirements
To construct viable business process models using the Graphical Process Modeler, you must use certain Business Process Modeling Language activities according to requirements related to their placement in your process models.
Some activities must be used in pairs, to bracket other activities. That is, for a given activity, you must use one of these bracketing, or parent, activities at the beginning and one at the end. For example, before a series of activities in a business process model that you intend to run simultaneously, you must include the All Start BPML activity, and after the series, you must include the All End activity. For a complete list of available BPML activities depicted in the GPM, and the requirements related to using them, see BPML Activities in Business Process Models.