diff --git a/engine-rest/engine-rest-openapi/src/main/templates/models/org/camunda/bpm/engine/rest/dto/runtime/ProcessInstanceDto.ftl b/engine-rest/engine-rest-openapi/src/main/templates/models/org/camunda/bpm/engine/rest/dto/runtime/ProcessInstanceDto.ftl
index 57919f2efc7..1354424122d 100644
--- a/engine-rest/engine-rest-openapi/src/main/templates/models/org/camunda/bpm/engine/rest/dto/runtime/ProcessInstanceDto.ftl
+++ b/engine-rest/engine-rest-openapi/src/main/templates/models/org/camunda/bpm/engine/rest/dto/runtime/ProcessInstanceDto.ftl
@@ -12,6 +12,14 @@
         type = "string"
         desc = "The id of the process definition that this process instance belongs to." />
 
+   <#-- 
+    GIT Issue : https://github.com/camunda/camunda-bpm-platform/issues/4049 
+    -->    
+    <@lib.property
+        name = "definitionKey"
+        type = "string"
+        desc = "The key of the process definition that this process instance belongs to." />
+
     <@lib.property
         name = "businessKey"
         type = "string"
@@ -40,4 +48,4 @@
         desc = "The tenant id of the process instance." />
 
 </@lib.dto>
-</#macro>
\ No newline at end of file
+</#macro>
diff --git a/engine-rest/engine-rest-openapi/src/main/templates/paths/process-definition/{id}/start/post.ftl b/engine-rest/engine-rest-openapi/src/main/templates/paths/process-definition/{id}/start/post.ftl
index 15d5b9e358d..e1bad79d9d5 100644
--- a/engine-rest/engine-rest-openapi/src/main/templates/paths/process-definition/{id}/start/post.ftl
+++ b/engine-rest/engine-rest-openapi/src/main/templates/paths/process-definition/{id}/start/post.ftl
@@ -113,6 +113,7 @@
                          ],
                          "id":"anId",
                          "definitionId":"aProcessDefinitionId",
+                         "definitionKey":"aProcessDefinitionKey",
                          "businessKey":"myBusinessKey",
                          "caseInstanceId": null,
                          "tenantId":null,
@@ -133,6 +134,7 @@
                          ],
                          "id": "aProcInstId",
                          "definitionId": "aProcessDefinitionId",
+                         "definitionKey": "aProcessDefinitionKey",
                          "businessKey": "myBusinessKey",
                          "caseInstanceId": null,
                          "ended": false,
@@ -167,6 +169,7 @@
                          ],
                          "id":"anId",
                          "definitionId":"aProcessDefinitionId",
+                         "definitionKey":"aProcessDefinitionKey",
                          "businessKey":"myBusinessKey",
                          "caseInstanceId": null,
                          "tenantId":null,
@@ -195,4 +198,4 @@
   }
 }
 
-</#macro>
\ No newline at end of file
+</#macro>
diff --git a/engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/get.ftl b/engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/get.ftl
index 307a176bebf..de25976f184 100644
--- a/engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/get.ftl
+++ b/engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/get.ftl
@@ -34,6 +34,7 @@
                            "links": [],
                            "id": "anId",
                            "definitionId": "aProcDefId",
+                           "definitionKey": "aProcDefKey",
                            "businessKey": "aKey",
                            "caseInstanceId": "aCaseInstanceId",
                            "ended": false,
@@ -53,4 +54,4 @@
   }
 }
 
-</#macro>
\ No newline at end of file
+</#macro>
diff --git a/engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/post.ftl b/engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/post.ftl
index 2b071dc7a2d..a52e08a5c82 100644
--- a/engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/post.ftl
+++ b/engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/post.ftl
@@ -60,6 +60,7 @@
                            "links": [],
                            "id": "anId",
                            "definitionId": "aProcessDefinitionId",
+                           "definitionKey": "aProcessDefinitionKey",
                            "businessKey": "aKey",
                            "caseInstanceId": "aCaseInstanceId",
                            "ended": false,
@@ -80,4 +81,4 @@
   }
 }
 
-</#macro>
\ No newline at end of file
+</#macro>
diff --git a/engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/{id}/get.ftl b/engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/{id}/get.ftl
index 7f89c4bafe9..933bdffa4c4 100644
--- a/engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/{id}/get.ftl
+++ b/engine-rest/engine-rest-openapi/src/main/templates/paths/process-instance/{id}/get.ftl
@@ -28,6 +28,7 @@
                        "value": {
                          "id":"aProcessInstanceId",
                          "definitionId":"aProcDefId",
+                         "definitionKey":"aProcDefKey",
                          "businessKey":"aKey",
                          "caseInstanceId":"aCaseInstanceId",
                          "ended":false,
@@ -45,4 +46,4 @@
 
   }
 }
-</#macro>
\ No newline at end of file
+</#macro>
diff --git a/engine-rest/engine-rest/src/main/java/org/camunda/bpm/engine/rest/dto/runtime/ProcessInstanceDto.java b/engine-rest/engine-rest/src/main/java/org/camunda/bpm/engine/rest/dto/runtime/ProcessInstanceDto.java
index e7461c640ea..93ba9037470 100644
--- a/engine-rest/engine-rest/src/main/java/org/camunda/bpm/engine/rest/dto/runtime/ProcessInstanceDto.java
+++ b/engine-rest/engine-rest/src/main/java/org/camunda/bpm/engine/rest/dto/runtime/ProcessInstanceDto.java
@@ -28,6 +28,7 @@ public class ProcessInstanceDto extends LinkableDto {
   private boolean ended;
   private boolean suspended;
   private String tenantId;
+  private String definitionKey;
 
   public ProcessInstanceDto() {
   }
@@ -35,6 +36,7 @@ public ProcessInstanceDto() {
   public ProcessInstanceDto(ProcessInstance instance) {
     this.id = instance.getId();
     this.definitionId = instance.getProcessDefinitionId();
+    this.definitionKey = instance.getProcessDefinitionKey();
     this.businessKey = instance.getBusinessKey();
     this.caseInstanceId = instance.getCaseInstanceId();
     this.ended = instance.isEnded();
@@ -49,6 +51,14 @@ public String getId() {
   public String getDefinitionId() {
     return definitionId;
   }
+  
+ /**
+ * @return the definitionKey
+ * GIT Issue : https://github.com/camunda/camunda-bpm-platform/issues/4049
+ */
+  public String getDefinitionKey() {
+	return definitionKey;
+  }
 
   public String getBusinessKey() {
     return businessKey;
diff --git a/engine-rest/engine-rest/src/test/java/org/camunda/bpm/engine/rest/ProcessInstanceRestServiceInteractionTest.java b/engine-rest/engine-rest/src/test/java/org/camunda/bpm/engine/rest/ProcessInstanceRestServiceInteractionTest.java
index 345be01068e..7bcf0d9750d 100644
--- a/engine-rest/engine-rest/src/test/java/org/camunda/bpm/engine/rest/ProcessInstanceRestServiceInteractionTest.java
+++ b/engine-rest/engine-rest/src/test/java/org/camunda/bpm/engine/rest/ProcessInstanceRestServiceInteractionTest.java
@@ -1083,6 +1083,7 @@ public void testGetSingleInstance() {
       .body("id", Matchers.equalTo(MockProvider.EXAMPLE_PROCESS_INSTANCE_ID))
       .body("ended", Matchers.equalTo(MockProvider.EXAMPLE_PROCESS_INSTANCE_IS_ENDED))
       .body("definitionId", Matchers.equalTo(MockProvider.EXAMPLE_PROCESS_DEFINITION_ID))
+      .body("definitionKey", Matchers.equalTo(MockProvider.EXAMPLE_PROCESS_DEFINITION_KEY))
       .body("businessKey", Matchers.equalTo(MockProvider.EXAMPLE_PROCESS_INSTANCE_BUSINESS_KEY))
       .body("suspended", Matchers.equalTo(MockProvider.EXAMPLE_PROCESS_INSTANCE_IS_SUSPENDED))
       .body("tenantId", Matchers.equalTo(MockProvider.EXAMPLE_TENANT_ID))
diff --git a/engine-rest/engine-rest/src/test/java/org/camunda/bpm/engine/rest/helper/MockProvider.java b/engine-rest/engine-rest/src/test/java/org/camunda/bpm/engine/rest/helper/MockProvider.java
index 4a4a312996e..7c9e2d6bca8 100644
--- a/engine-rest/engine-rest/src/test/java/org/camunda/bpm/engine/rest/helper/MockProvider.java
+++ b/engine-rest/engine-rest/src/test/java/org/camunda/bpm/engine/rest/helper/MockProvider.java
@@ -1302,6 +1302,7 @@ public static ProcessInstance createMockInstance(String tenantId) {
     when(mock.getBusinessKey()).thenReturn(EXAMPLE_PROCESS_INSTANCE_BUSINESS_KEY);
     when(mock.getCaseInstanceId()).thenReturn(EXAMPLE_CASE_INSTANCE_ID);
     when(mock.getProcessDefinitionId()).thenReturn(EXAMPLE_PROCESS_DEFINITION_ID);
+    when(mock.getProcessDefinitionKey()).thenReturn(EXAMPLE_PROCESS_DEFINITION_KEY);
     when(mock.getProcessInstanceId()).thenReturn(EXAMPLE_PROCESS_INSTANCE_ID);
     when(mock.isSuspended()).thenReturn(EXAMPLE_PROCESS_INSTANCE_IS_SUSPENDED);
     when(mock.isEnded()).thenReturn(EXAMPLE_PROCESS_INSTANCE_IS_ENDED);
diff --git a/engine/src/main/java/org/camunda/bpm/engine/impl/cmd/StartProcessInstanceCmd.java b/engine/src/main/java/org/camunda/bpm/engine/impl/cmd/StartProcessInstanceCmd.java
index ccb5c0328af..295f777c8e8 100644
--- a/engine/src/main/java/org/camunda/bpm/engine/impl/cmd/StartProcessInstanceCmd.java
+++ b/engine/src/main/java/org/camunda/bpm/engine/impl/cmd/StartProcessInstanceCmd.java
@@ -61,6 +61,8 @@ public ProcessInstanceWithVariables execute(CommandContext commandContext) {
       processInstance.setTenantId(instantiationBuilder.getTenantId());
     }
 
+    processInstance.setProcessDefinitionKey(processDefinition.getKey());
+
     final ExecutionVariableSnapshotObserver variablesListener = new ExecutionVariableSnapshotObserver(processInstance);
 
     processInstance.start(instantiationBuilder.getVariables());
diff --git a/engine/src/main/java/org/camunda/bpm/engine/impl/persistence/entity/ExecutionEntity.java b/engine/src/main/java/org/camunda/bpm/engine/impl/persistence/entity/ExecutionEntity.java
index a97d1922c31..30f3ba9075e 100644
--- a/engine/src/main/java/org/camunda/bpm/engine/impl/persistence/entity/ExecutionEntity.java
+++ b/engine/src/main/java/org/camunda/bpm/engine/impl/persistence/entity/ExecutionEntity.java
@@ -234,6 +234,11 @@ public class ExecutionEntity extends PvmExecutionImpl implements Execution, Proc
    */
   protected String superCaseExecutionId;
 
+  /**
+   * The name of the process definition key
+   */
+  protected String processDefinitionKey;
+
   /**
    * Contains observers which are observe the execution.
    * @since 7.6
@@ -263,6 +268,7 @@ public ExecutionEntity createExecution() {
 
     // initialize the new execution
     createdExecution.setProcessDefinition(getProcessDefinition());
+    createdExecution.setProcessDefinitionKey(getProcessDefinitionKey());
     createdExecution.setProcessInstance(getProcessInstance());
     createdExecution.setActivity(getActivity());
     createdExecution.setSuspensionState(getSuspensionState());
@@ -1935,4 +1941,13 @@ public ProcessEngine getProcessEngine() {
   public String getProcessDefinitionTenantId() {
     return getProcessDefinition().getTenantId();
   }
+
+   public void setProcessDefinitionKey(String processDefinitionKey) {
+     this.processDefinitionKey = processDefinitionKey;
+  }
+   
+  public String getProcessDefinitionKey() {
+    return processDefinitionKey;
+  }
+  
 }
diff --git a/engine/src/main/java/org/camunda/bpm/engine/impl/persistence/entity/ProcessInstanceWithVariablesImpl.java b/engine/src/main/java/org/camunda/bpm/engine/impl/persistence/entity/ProcessInstanceWithVariablesImpl.java
index 080c6c8705a..479f304b052 100644
--- a/engine/src/main/java/org/camunda/bpm/engine/impl/persistence/entity/ProcessInstanceWithVariablesImpl.java
+++ b/engine/src/main/java/org/camunda/bpm/engine/impl/persistence/entity/ProcessInstanceWithVariablesImpl.java
@@ -86,4 +86,9 @@ public String getProcessInstanceId() {
   public String getTenantId() {
     return executionEntity.getTenantId();
   }
+ 
+  @Override
+  public String getProcessDefinitionKey() {
+    return executionEntity.getProcessDefinitionKey();
+  }
 }
diff --git a/engine/src/main/java/org/camunda/bpm/engine/runtime/Execution.java b/engine/src/main/java/org/camunda/bpm/engine/runtime/Execution.java
index 2c78e6b6e4c..1cbae07dd64 100644
--- a/engine/src/main/java/org/camunda/bpm/engine/runtime/Execution.java
+++ b/engine/src/main/java/org/camunda/bpm/engine/runtime/Execution.java
@@ -52,4 +52,9 @@ public interface Execution {
    */
   String getTenantId();
 
+  /**
+   * The Key of the process definition.
+   */
+  String getProcessDefinitionKey();
+
 }
diff --git a/engine/src/main/java/org/camunda/bpm/engine/runtime/ProcessInstance.java b/engine/src/main/java/org/camunda/bpm/engine/runtime/ProcessInstance.java
index d8a07d494aa..dd2bbed9e71 100644
--- a/engine/src/main/java/org/camunda/bpm/engine/runtime/ProcessInstance.java
+++ b/engine/src/main/java/org/camunda/bpm/engine/runtime/ProcessInstance.java
@@ -32,6 +32,11 @@ public interface ProcessInstance extends Execution {
    */
   String getProcessDefinitionId();
 
+  /**
+   * The key of the process definition of the process instance.
+   */
+  String getProcessDefinitionKey();
+
   /**
    * The business key of this process instance.
    */
diff --git a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.cockroachdb.create.engine.sql b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.cockroachdb.create.engine.sql
index 7789480cd53..1b557ea64f3 100644
--- a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.cockroachdb.create.engine.sql
+++ b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.cockroachdb.create.engine.sql
@@ -101,6 +101,7 @@ create table ACT_RU_EXECUTION (
     CACHED_ENT_STATE_ integer,
     SEQUENCE_COUNTER_ bigint,
     TENANT_ID_ varchar(64),
+    PROC_DEF_KEY_ varchar(255),
     primary key (ID_)
 );
 
@@ -593,4 +594,4 @@ create index ACT_IDX_PROCDEF_VER_TAG ON ACT_RE_PROCDEF(VERSION_TAG_);
 
 -- indices for history cleanup: https://jira.camunda.com/browse/CAM-11616
 create index ACT_IDX_AUTH_ROOT_PI on ACT_RU_AUTHORIZATION(ROOT_PROC_INST_ID_);
-create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
\ No newline at end of file
+create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
diff --git a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.db2.create.engine.sql b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.db2.create.engine.sql
index 4f61d68326d..bc1245a6c67 100644
--- a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.db2.create.engine.sql
+++ b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.db2.create.engine.sql
@@ -101,6 +101,7 @@ create table ACT_RU_EXECUTION (
     CACHED_ENT_STATE_ integer,
     SEQUENCE_COUNTER_ bigint,
     TENANT_ID_ varchar(64),
+    PROC_DEF_KEY_ varchar(255),
     primary key (ID_)
 );
 
@@ -594,4 +595,4 @@ create index ACT_IDX_PROCDEF_VER_TAG ON ACT_RE_PROCDEF(VERSION_TAG_);
 
 -- indices for history cleanup: https://jira.camunda.com/browse/CAM-11616
 create index ACT_IDX_AUTH_ROOT_PI on ACT_RU_AUTHORIZATION(ROOT_PROC_INST_ID_);
-create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
\ No newline at end of file
+create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
diff --git a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.h2.create.engine.sql b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.h2.create.engine.sql
index 72f0d2b6b4f..3e37ed9d3e1 100644
--- a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.h2.create.engine.sql
+++ b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.h2.create.engine.sql
@@ -101,6 +101,7 @@ create table ACT_RU_EXECUTION (
     CACHED_ENT_STATE_ integer,
     SEQUENCE_COUNTER_ integer,
     TENANT_ID_ varchar(64),
+    PROC_DEF_KEY_ varchar(255),
     primary key (ID_)
 );
 
@@ -585,4 +586,4 @@ alter table ACT_RU_VARIABLE
 
 -- indices for history cleanup: https://jira.camunda.com/browse/CAM-11616
 create index ACT_IDX_AUTH_ROOT_PI on ACT_RU_AUTHORIZATION(ROOT_PROC_INST_ID_);
-create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
\ No newline at end of file
+create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
diff --git a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.mariadb.create.engine.sql b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.mariadb.create.engine.sql
index 746203df164..86e2175a1cc 100644
--- a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.mariadb.create.engine.sql
+++ b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.mariadb.create.engine.sql
@@ -101,6 +101,7 @@ create table ACT_RU_EXECUTION (
     CACHED_ENT_STATE_ integer,
     SEQUENCE_COUNTER_ bigint,
     TENANT_ID_ varchar(64),
+    PROC_DEF_KEY_ varchar(255),
     primary key (ID_)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE utf8_bin;
 
@@ -586,4 +587,4 @@ create index ACT_IDX_PROCDEF_VER_TAG ON ACT_RE_PROCDEF(VERSION_TAG_);
 
 -- indices for history cleanup: https://jira.camunda.com/browse/CAM-11616
 create index ACT_IDX_AUTH_ROOT_PI on ACT_RU_AUTHORIZATION(ROOT_PROC_INST_ID_);
-create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
\ No newline at end of file
+create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
diff --git a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.mssql.create.engine.sql b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.mssql.create.engine.sql
index e8bf58836f1..aebe2e5738c 100644
--- a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.mssql.create.engine.sql
+++ b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.mssql.create.engine.sql
@@ -101,6 +101,7 @@ create table ACT_RU_EXECUTION (
     CACHED_ENT_STATE_ int,
     SEQUENCE_COUNTER_ numeric(19,0),
     TENANT_ID_ nvarchar(64),
+    PROC_DEF_KEY_ nvarchar(255),
     primary key (ID_)
 );
 
@@ -590,4 +591,4 @@ create index ACT_IDX_PROCDEF_VER_TAG ON ACT_RE_PROCDEF(VERSION_TAG_);
 
 -- indices for history cleanup: https://jira.camunda.com/browse/CAM-11616
 create index ACT_IDX_AUTH_ROOT_PI on ACT_RU_AUTHORIZATION(ROOT_PROC_INST_ID_);
-create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
\ No newline at end of file
+create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
diff --git a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.mysql.create.engine.sql b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.mysql.create.engine.sql
index 4c7965866ef..256104301a0 100644
--- a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.mysql.create.engine.sql
+++ b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.mysql.create.engine.sql
@@ -101,6 +101,7 @@ create table ACT_RU_EXECUTION (
     CACHED_ENT_STATE_ integer,
     SEQUENCE_COUNTER_ bigint,
     TENANT_ID_ varchar(64),
+    PROC_DEF_KEY_ varchar(255),    
     primary key (ID_)
 ) ENGINE=InnoDB DEFAULT CHARSET=utf8 COLLATE utf8_bin;
 
@@ -586,4 +587,4 @@ create index ACT_IDX_PROCDEF_VER_TAG ON ACT_RE_PROCDEF(VERSION_TAG_);
 
 -- indices for history cleanup: https://jira.camunda.com/browse/CAM-11616
 create index ACT_IDX_AUTH_ROOT_PI on ACT_RU_AUTHORIZATION(ROOT_PROC_INST_ID_);
-create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
\ No newline at end of file
+create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
diff --git a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.oracle.create.engine.sql b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.oracle.create.engine.sql
index 503ec586d99..ce175997e61 100644
--- a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.oracle.create.engine.sql
+++ b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.oracle.create.engine.sql
@@ -101,6 +101,7 @@ create table ACT_RU_EXECUTION (
     CACHED_ENT_STATE_ INTEGER,
     SEQUENCE_COUNTER_ NUMBER(19,0),
     TENANT_ID_ NVARCHAR2(64),
+    PROC_DEF_KEY_ NVARCHAR2(255),
     primary key (ID_)
 );
 
@@ -605,4 +606,4 @@ create index ACT_IDX_PROCDEF_VER_TAG ON ACT_RE_PROCDEF(VERSION_TAG_);
 
 -- indices for history cleanup: https://jira.camunda.com/browse/CAM-11616
 create index ACT_IDX_AUTH_ROOT_PI on ACT_RU_AUTHORIZATION(ROOT_PROC_INST_ID_);
-create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
\ No newline at end of file
+create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
diff --git a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.postgres.create.engine.sql b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.postgres.create.engine.sql
index e3a8b24a4e3..db5e050e0d8 100644
--- a/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.postgres.create.engine.sql
+++ b/engine/src/main/resources/org/camunda/bpm/engine/db/create/activiti.postgres.create.engine.sql
@@ -101,6 +101,7 @@ create table ACT_RU_EXECUTION (
     CACHED_ENT_STATE_ integer,
     SEQUENCE_COUNTER_ bigint,
     TENANT_ID_ varchar(64),
+    PROC_DEF_KEY_ varchar(255),
     primary key (ID_)
 );
 
@@ -600,4 +601,4 @@ create index ACT_IDX_PROCDEF_VER_TAG ON ACT_RE_PROCDEF(VERSION_TAG_);
 
 -- indices for history cleanup: https://jira.camunda.com/browse/CAM-11616
 create index ACT_IDX_AUTH_ROOT_PI on ACT_RU_AUTHORIZATION(ROOT_PROC_INST_ID_);
-create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
\ No newline at end of file
+create index ACT_IDX_AUTH_RM_TIME on ACT_RU_AUTHORIZATION(REMOVAL_TIME_);
diff --git a/engine/src/main/resources/org/camunda/bpm/engine/impl/mapping/entity/Execution.xml b/engine/src/main/resources/org/camunda/bpm/engine/impl/mapping/entity/Execution.xml
index 83e03d773e4..97626c9bded 100644
--- a/engine/src/main/resources/org/camunda/bpm/engine/impl/mapping/entity/Execution.xml
+++ b/engine/src/main/resources/org/camunda/bpm/engine/impl/mapping/entity/Execution.xml
@@ -45,10 +45,10 @@
       CACHED_ENT_STATE_,
       SEQUENCE_COUNTER_,
       TENANT_ID_,
+      PROC_DEF_KEY_,
       REV_
     )
-    values
-    (
+    values    (
       #{id ,jdbcType=VARCHAR},
       #{rootProcessInstanceIdRaw, jdbcType=VARCHAR},
       #{processInstanceId, jdbcType=VARCHAR},
@@ -68,6 +68,7 @@
       #{cachedEntityState, jdbcType=INTEGER},
       #{sequenceCounter, jdbcType=BIGINT},
       #{tenantId, jdbcType=VARCHAR},
+      #{processDefinitionKey, jdbcType=VARCHAR},
       1
     )
   </insert>
@@ -90,7 +91,8 @@
       SUSPENSION_STATE_ = #{suspensionState, jdbcType=INTEGER},
       CACHED_ENT_STATE_ = #{cachedEntityState, jdbcType=INTEGER},
       SEQUENCE_COUNTER_ = #{sequenceCounter, jdbcType=BIGINT},
-      TENANT_ID_ = #{tenantId, jdbcType=BIGINT}
+      TENANT_ID_ = #{tenantId, jdbcType=BIGINT},
+      PROC_DEF_KEY_ = #{processDefinitionKey, jdbcType=VARCHAR}
     where ID_ = #{id, jdbcType=VARCHAR}
       and REV_ = #{revision, jdbcType=INTEGER}
   </update>
@@ -155,6 +157,7 @@
     <result property="cachedEntityState" column="CACHED_ENT_STATE_" jdbcType="INTEGER"/>
     <result property="sequenceCounter" column="SEQUENCE_COUNTER_" jdbcType="BIGINT"/>
     <result property="tenantId" column="TENANT_ID_" jdbcType="VARCHAR"/>
+    <result property="processDefinitionKey" column="PROC_DEF_KEY_" jdbcType="VARCHAR"/>   
   </resultMap>
   
   <resultMap type="org.camunda.bpm.engine.impl.util.ImmutablePair" id="deploymentIdMapping">
diff --git a/engine/src/test/java/org/camunda/bpm/engine/test/api/runtime/ExecutionQueryTest.java b/engine/src/test/java/org/camunda/bpm/engine/test/api/runtime/ExecutionQueryTest.java
index d73785530cc..bc79a0d3b6e 100644
--- a/engine/src/test/java/org/camunda/bpm/engine/test/api/runtime/ExecutionQueryTest.java
+++ b/engine/src/test/java/org/camunda/bpm/engine/test/api/runtime/ExecutionQueryTest.java
@@ -98,6 +98,7 @@ public void testQueryByProcessDefinitionKey() {
     // Concurrent process with 3 executions for each process instance
     assertEquals(12, runtimeService.createExecutionQuery().processDefinitionKey(CONCURRENT_PROCESS_KEY).list().size());
     assertEquals(1, runtimeService.createExecutionQuery().processDefinitionKey(SEQUENTIAL_PROCESS_KEY).list().size());
+    assertNotNull(runtimeService.createExecutionQuery().processDefinitionKey(SEQUENTIAL_PROCESS_KEY).singleResult().getProcessDefinitionKey());
   }
 
   @Test
diff --git a/engine/src/test/java/org/camunda/bpm/engine/test/standalone/entity/ExecutionEntityTest.java b/engine/src/test/java/org/camunda/bpm/engine/test/standalone/entity/ExecutionEntityTest.java
index 94bd35929df..d1a777fb070 100644
--- a/engine/src/test/java/org/camunda/bpm/engine/test/standalone/entity/ExecutionEntityTest.java
+++ b/engine/src/test/java/org/camunda/bpm/engine/test/standalone/entity/ExecutionEntityTest.java
@@ -109,6 +109,7 @@ public void testRemoveExecutionSequence() {
     // when
     assertNotNull(execution);
     assertEquals(pi.getId(), execution.getProcessInstanceId());
+    assertEquals(pi.getProcessDefinitionKey(), execution.getProcessDefinitionKey());
     processEngineRule.getRuntimeService().signal(execution.getId());
 
     // then (see #TestLocalVariableTaskListener::notify)
diff --git a/engine/src/test/java/org/camunda/bpm/engine/test/util/ExecutionTree.java b/engine/src/test/java/org/camunda/bpm/engine/test/util/ExecutionTree.java
index a35e07aeb7b..189410b1496 100644
--- a/engine/src/test/java/org/camunda/bpm/engine/test/util/ExecutionTree.java
+++ b/engine/src/test/java/org/camunda/bpm/engine/test/util/ExecutionTree.java
@@ -176,4 +176,9 @@ protected static String executionTreeToString(ExecutionTree executionTree) {
     return sb.toString();
   }
 
+  @Override
+  public String getProcessDefinitionKey() {
+    return wrappedExecution.getProcessDefinitionKey();
+  }
+
 }