A call activity identifies a point in the process where a global process or a global task is used. The call activity acts as a ‘wrapper’ for the invocation of a global process or global task within the execution. The activation of a call activity results in the transfer of control to the called global process or global task.

The BPMN 2.0 call activity corresponds to the reusable sub-process of BPMN 1.2. A BPMN 2.0 sub-process corresponds to the embedded sub-process of BPMN 1.2.

A call activity object shares the same shape as the task and sub-process, which is a rectangle that has rounded corners. However, the target of what the activity calls will determine the details of its shape.

• If the call activity calls a global task, then the shape will be the same as a task, but the boundary of the shape MUST have a thick line.
  The call activity MUST display the marker of the type of global task (e.g., the call activity would display the user task marker if calling a global user task).

• If the call activity calls a process, then there are two (2) options:
  • The details of the called process can be hidden and the shape of the call activity will be the same as a collapsed sub-process, but the boundary of the shape MUST have a thick line.
  • If the details of the called process are available, then the shape of the call activity will be the same as an expanded sub-process, but the boundary of the shape MUST have a thick line.

A global task is a reusable, atomic task definition that can be called from within any process by a call activity.