---
title: "13.2 Process Instantiation and Termination"
chapter: "13 BPMN Execution Semantics"
source: "OMG BPMN 2.0.2 — formal/2013-12-09"
pages: "426"
---

> 13 BPMN Execution Semantics · páginas 426 · [índice](../README.md)


<a id="sec-13-2"></a>
## 13.2 Process Instantiation and Termination


A **Process** is instantiated when one of its **Start Events** occurs. Each occurrence of a **Start Event** creates a new **Process** *Instance* unless the **Start Event** participates in a **Conversation** that includes other **Start Events**. In that case, a new **Process** *instance* is only created if none already exists for the specific **Conversation** (identified through its associated correlation information) of the **Event** occurrence. Subsequent **Start Events** that share the same correlation information as a **Start Event** that created a **Process** *instance* are routed to that **Process** *instance*. Note that a *global* **Process** MUST neither have any empty **Start Event** nor any **Gateway** or **Activity** without *incoming* **Sequence Flows**. An exception is the **Event Gateway**. A **Process** can also be started via an **Event-Based Gateway** or a **Receive Task** that has no *incoming* **Sequence Flows** and its instantiate flag set to *true*. If the **Event-Based Gateway** is *exclusive*, the first matching **Event** will create a new *instance* of the **Process**. The **Process** then does not wait for the other **Events** originating from the same **Event-Based Gateway** (see also semantics of the **Event-Based Exclusive Gateway** on page 437). If the **Event-Based Gateway** is *parallel*, also the first matching **Event** creates a new **Process** *instance*. However, the **Process** then waits for the other **Events** to arrive. As stated above, those **Events** MUST have the same correlation information as the **Event** that arrived first. A **Process** *instance* completes only if all **Events** that succeed a **Parallel Event-Based Gateway** have occurred. To specify that the instantiation of a **Process** waits for multiple **Start Events** to happen, a **Multiple Parallel Start Event** can be used. Note that two **Start Events** are alternative, A **Process** *instance* triggered by one of the **Start Events** does not wait for an alternative **Start Event** to occur. Note that there MAY be multiple instantiating **Parallel Event-Based Gateways**. This allows the modeler to express that either all the **Events** after the first **Gateway** occur or all the **Events** after the second **Gateway** and so forth. Each **Start Event** that occurs creates a *token* on its *outgoing* **Sequence Flows**, which is followed as described by the semantics of the other **Process** elements. A **Process** *instance* is completed, if and only if the following three conditions hold:


For a **Process** *instance* to become completed, all *tokens* in that *instance* MUST reach an end node, i.e., a node without *outgoing* **Sequence Flows**. A *token* reaching an **End Event** triggers the behavior associated with the **Event** type, e.g., the associated **Message** is sent for a **Message End Event**, the associated *Signal* is sent for a **Signal End Event**, and so on. If a *token* reaches a **Terminate End Event**, the entire **Process** is abnormally terminated.