diff --git a/application-engine/src/main/java/com/netgrif/application/engine/workflow/domain/repositories/TaskRepository.java b/application-engine/src/main/java/com/netgrif/application/engine/workflow/domain/repositories/TaskRepository.java
index 5338d1d4ab..019b2d1bac 100644
--- a/application-engine/src/main/java/com/netgrif/application/engine/workflow/domain/repositories/TaskRepository.java
+++ b/application-engine/src/main/java/com/netgrif/application/engine/workflow/domain/repositories/TaskRepository.java
@@ -26,9 +26,9 @@ public interface TaskRepository extends MongoRepository<Task, String>, QuerydslP
 
     List<Task> findAllByTransitionIdIn(Collection<String> ids);
 
-    Page<Task> findByUserId(Pageable pageable, String userId);
+    Page<Task> findByAssignee_Id(Pageable pageable, String userId);
 
-    List<Task> findByUserIdAndFinishDateNotNull(Long userId);
+    List<Task> findByAssignee_IdAndFinishDateNotNull(String userId);
 
     Task findByTransitionIdAndCaseId(String transitionId, String caseId);
 
@@ -36,7 +36,7 @@ public interface TaskRepository extends MongoRepository<Task, String>, QuerydslP
 
     List<Task> findAllBy_idIn(Iterable<ProcessResourceId> id);
 
-    void deleteAllByCaseIdAndUserIdIsNull(String caseId);
+    void deleteAllByCaseIdAndAssignee_IdIsNull(String caseId);
 
     void deleteAllByCaseIdAndFinishDateIsNotNull(String caseId);
 
diff --git a/application-engine/src/main/java/com/netgrif/application/engine/workflow/service/TaskSearchService.java b/application-engine/src/main/java/com/netgrif/application/engine/workflow/service/TaskSearchService.java
index f887e87dd8..fb03f39944 100644
--- a/application-engine/src/main/java/com/netgrif/application/engine/workflow/service/TaskSearchService.java
+++ b/application-engine/src/main/java/com/netgrif/application/engine/workflow/service/TaskSearchService.java
@@ -221,7 +221,7 @@ private void buildUserQuery(TaskSearchRequest request, BooleanBuilder query) {
     }
 
     public Predicate userQuery(String userId) {
-        return QTask.task.userId.eq(userId);
+        return QTask.task.assignee.id.eq(userId);
     }
 
     private void buildProcessQuery(TaskSearchRequest request, BooleanBuilder query) {
diff --git a/application-engine/src/main/java/com/netgrif/application/engine/workflow/service/TaskService.java b/application-engine/src/main/java/com/netgrif/application/engine/workflow/service/TaskService.java
index d54ca85a7a..26be3a46e3 100644
--- a/application-engine/src/main/java/com/netgrif/application/engine/workflow/service/TaskService.java
+++ b/application-engine/src/main/java/com/netgrif/application/engine/workflow/service/TaskService.java
@@ -2,6 +2,7 @@
 
 import com.google.common.collect.Ordering;
 import com.netgrif.application.engine.objects.auth.domain.AbstractUser;
+import com.netgrif.application.engine.objects.auth.domain.ActorTransformer;
 import com.netgrif.application.engine.objects.auth.domain.LoggedUser;
 import com.netgrif.application.engine.auth.service.UserService;
 import com.netgrif.application.engine.elastic.service.interfaces.IElasticTaskMappingService;
@@ -166,8 +167,7 @@ protected Case assignTaskToUser(AbstractUser user, Task task, Case useCase, Tran
 
         startExecution(transition, useCase);
         // TODO: impersonation
-        task.setUserId(user.getStringId());
-        task.setUserRealmId(user.getRealmId());
+        task.setAssignee(ActorTransformer.toActorRef(user));
         task.setStartDate(LocalDateTime.now());
         // TODO: impersonation
         task.setUser(user);
@@ -398,8 +398,7 @@ private Case returnTokens(Task task, Case useCase) {
                 });
         workflowService.updateMarking(useCase);
 
-        task.setUserId(null);
-        task.setUserRealmId(null);
+        task.setAssignee(null);
         task.setStartDate(null);
 
         useCase = workflowService.save(useCase);
@@ -452,8 +451,7 @@ public DelegateTaskEventOutcome delegateTask(DelegateTaskParams delegateTaskPara
 
     protected Case delegate(AbstractUser delegated, Task task, Case useCase, Transition transition) throws TransitionNotExecutableException {
         if (task.getUserId() != null) {
-            task.setUserId(delegated.getStringId());
-            task.setUserRealmId(delegated.getRealmId());
+            task.setAssignee(ActorTransformer.toActorRef(delegated));
             task.setUser(delegated);
             save(task);
             return useCase;
@@ -572,8 +570,7 @@ protected Case finishExecution(Transition transition, Task task, Case useCase) t
 
         task.setFinishDate(LocalDateTime.now());
         task.setFinishedBy(task.getUserId());
-        task.setUserId(null);
-        task.setUserRealmId(null);
+        task.setAssignee(null);
 
         save(task);
         return workflowService.save(useCase);
@@ -762,7 +759,7 @@ public List<Task> findAllById(List<String> ids) {
     public Page<Task> findByUser(Pageable pageable, AbstractUser user) {
         // TODO: impersonation
 //        return loadUsers(taskRepository.findByUserId(pageable, user.getSelfOrImpersonated().getStringId()));
-        return loadUsers(taskRepository.findByUserId(pageable, user.getStringId()));
+        return loadUsers(taskRepository.findByAssignee_Id(pageable, user.getStringId()));
     }
 
     @Override
diff --git a/application-engine/src/main/java/com/netgrif/application/engine/workflow/web/responsebodies/Task.java b/application-engine/src/main/java/com/netgrif/application/engine/workflow/web/responsebodies/Task.java
index b226b7e889..d261e28cbf 100644
--- a/application-engine/src/main/java/com/netgrif/application/engine/workflow/web/responsebodies/Task.java
+++ b/application-engine/src/main/java/com/netgrif/application/engine/workflow/web/responsebodies/Task.java
@@ -1,6 +1,7 @@
 package com.netgrif.application.engine.workflow.web.responsebodies;
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
+import com.netgrif.application.engine.objects.auth.domain.ActorRef;
 import com.netgrif.application.engine.objects.elastic.domain.ElasticTask;
 import com.netgrif.application.engine.objects.petrinet.domain.dataset.Field;
 import com.netgrif.application.engine.objects.petrinet.domain.events.EventType;
@@ -36,9 +37,7 @@ public class Task {
 
     private Integer priority;
 
-    private String userId;
-
-    private String userRealmId;
+    private ActorRef assignee;
 
     private Map<String, Map<String, Boolean>> roles;
 
@@ -85,8 +84,7 @@ public Task(com.netgrif.application.engine.objects.workflow.domain.Task task, Lo
         this.caseColor = task.getCaseColor();
         this.caseTitle = task.getCaseTitle();
         this.priority = task.getPriority();
-        this.userId = task.getUser() != null ? task.getUser().getStringId() : null;
-        this.userRealmId = task.getUser() != null ? task.getUser().getRealmId() : null;
+        this.assignee = task.getAssignee();
         this.roles = task.getRoles();
         this.users = task.getUsers();
         this.startDate = task.getStartDate();
diff --git a/application-engine/src/test/groovy/com/netgrif/application/engine/ipc/TaskApiTest.groovy b/application-engine/src/test/groovy/com/netgrif/application/engine/ipc/TaskApiTest.groovy
index 0708b93a2b..b34a519ba9 100644
--- a/application-engine/src/test/groovy/com/netgrif/application/engine/ipc/TaskApiTest.groovy
+++ b/application-engine/src/test/groovy/com/netgrif/application/engine/ipc/TaskApiTest.groovy
@@ -230,7 +230,7 @@ class TaskApiTest {
         helper.assignTaskToSuper(TASK_BULK_TASK, control.stringId)
         helper.finishTaskAsSuper(TASK_BULK_TASK, control.stringId)
 
-        assert taskRepository.findAll(QTask.task.userId.eq(userService.system.getStringId())).size() == 2
+        assert taskRepository.findAll(QTask.task.assignee.id.eq(userService.system.getStringId())).size() == 2
     }
 
     public static final String TASK_GETTER_NET_FILE = "ipc_data.xml"
diff --git a/nae-object-library/src/main/java/com/netgrif/application/engine/objects/elastic/domain/ElasticTask.java b/nae-object-library/src/main/java/com/netgrif/application/engine/objects/elastic/domain/ElasticTask.java
index db7babc19e..db3616f9bf 100644
--- a/nae-object-library/src/main/java/com/netgrif/application/engine/objects/elastic/domain/ElasticTask.java
+++ b/nae-object-library/src/main/java/com/netgrif/application/engine/objects/elastic/domain/ElasticTask.java
@@ -51,6 +51,10 @@ public abstract class ElasticTask implements Serializable {
 
     private String userRealmId;
 
+    private String userFullName;
+    
+    private String username;
+
     private LocalDateTime startDate;
 
     private String transactionId;
@@ -93,8 +97,12 @@ public ElasticTask(Task task) {
         this.caseTitleSortable = this.caseTitle;
         if (task.getPriority() != null)
             this.priority = task.getPriority();
-        this.userId = task.getUserId();
-        this.userRealmId = task.getUserRealmId();
+        if (task.getAssignee() != null) {
+            this.userId = task.getAssignee().getId();
+            this.userRealmId = task.getAssignee().getRealmId();
+            this.username = task.getAssignee().getUsername();
+            this.userFullName = task.getAssignee().getFullName();
+        }
         this.startDate = task.getStartDate();
         this.roles = task.getRoles();
         this.userRefs = task.getUserRefs();
@@ -118,6 +126,8 @@ public void update(ElasticTask task) {
         this.priority = task.getPriority();
         this.userId = task.getUserId();
         this.userRealmId = task.getUserRealmId();
+        this.userFullName = task.getUserFullName();
+        this.username = task.getUsername();
         this.startDate = task.getStartDate();
         this.roles = task.getRoles();
         this.viewRoles = task.getViewRoles();
diff --git a/nae-object-library/src/main/java/com/netgrif/application/engine/objects/workflow/domain/Task.java b/nae-object-library/src/main/java/com/netgrif/application/engine/objects/workflow/domain/Task.java
index d1f5ea315c..f918b55c65 100644
--- a/nae-object-library/src/main/java/com/netgrif/application/engine/objects/workflow/domain/Task.java
+++ b/nae-object-library/src/main/java/com/netgrif/application/engine/objects/workflow/domain/Task.java
@@ -4,6 +4,7 @@
 import com.netgrif.application.engine.objects.annotations.Indexable;
 import com.netgrif.application.engine.objects.annotations.Indexed;
 import com.netgrif.application.engine.objects.auth.domain.AbstractUser;
+import com.netgrif.application.engine.objects.auth.domain.ActorRef;
 import com.netgrif.application.engine.objects.petrinet.domain.I18nString;
 import com.netgrif.application.engine.objects.petrinet.domain.dataset.Field;
 import com.netgrif.application.engine.objects.petrinet.domain.events.EventType;
@@ -69,12 +70,10 @@ public abstract class Task implements Serializable {
     @Setter
     private Integer priority;
 
+    @Getter
     @Setter
     @Indexed
-    private String userId;
-
-    @Setter
-    private String userRealmId;
+    private ActorRef assignee;
 
     @Getter
     @Setter
@@ -281,12 +280,12 @@ public void addEventTitle(EventType type, I18nString title) {
 
     @JsonIgnore
     public String getUserId() {
-        return userId;
+        return assignee != null ? assignee.getId() : null;
     }
 
     @JsonIgnore
     public String getUserRealmId() {
-        return userRealmId;
+        return assignee != null ? assignee.getRealmId() : null;
     }
 
     public String getTranslatedEventTitle(EventType assign, Locale locale) {
diff --git a/nae-spring-core-adapter/src/main/java/com/netgrif/application/engine/adapter/spring/workflow/domain/Task.java b/nae-spring-core-adapter/src/main/java/com/netgrif/application/engine/adapter/spring/workflow/domain/Task.java
index ce9702a0f9..1706fb4be9 100644
--- a/nae-spring-core-adapter/src/main/java/com/netgrif/application/engine/adapter/spring/workflow/domain/Task.java
+++ b/nae-spring-core-adapter/src/main/java/com/netgrif/application/engine/adapter/spring/workflow/domain/Task.java
@@ -2,6 +2,7 @@
 
 import com.fasterxml.jackson.annotation.JsonIgnore;
 import com.netgrif.application.engine.objects.auth.domain.AbstractUser;
+import com.netgrif.application.engine.objects.auth.domain.ActorRef;
 import com.netgrif.application.engine.objects.petrinet.domain.I18nString;
 import com.netgrif.application.engine.objects.petrinet.domain.dataset.Field;
 import com.netgrif.application.engine.objects.petrinet.domain.events.EventType;
@@ -29,8 +30,8 @@ public Task() {
     }
 
     @Builder(builderMethodName = "with")
-    public Task(ProcessResourceId _id, String processId, String caseId, String transitionId, TaskLayout layout, I18nString title, String caseColor, String caseTitle, Integer priority, String userId, String userRealmId, AbstractUser user, List<Trigger> triggers, Map<String, Map<String, Boolean>> roles, Map<String, Map<String, Boolean>> userRefs, Map<String, Map<String, Boolean>> users, List<String> viewRoles, List<String> viewUserRefs, List<String> viewUsers, List<String> negativeViewRoles, List<String> negativeViewUsers, LocalDateTime startDate, LocalDateTime finishDate, String finishedBy, String transactionId, Boolean requiredFilled, LinkedHashSet<String> immediateDataFields, List<Field<?>> immediateData, String icon, AssignPolicy assignPolicy, DataFocusPolicy dataFocusPolicy, FinishPolicy finishPolicy, Map<EventType, I18nString> eventTitles, Map<String, Boolean> assignedUserPolicy, Map<String, Integer> consumedTokens, Map<String, String> tags) {
-        super(_id, processId, caseId, transitionId, layout, title, caseColor, caseTitle, priority, userId, userRealmId, user, triggers, roles, userRefs, users, viewRoles, viewUserRefs, viewUsers, negativeViewRoles, negativeViewUsers, startDate, finishDate, finishedBy, transactionId, requiredFilled, immediateDataFields, immediateData, icon, assignPolicy, dataFocusPolicy, finishPolicy, eventTitles, assignedUserPolicy, consumedTokens, tags);
+    public Task(ProcessResourceId _id, String processId, String caseId, String transitionId, TaskLayout layout, I18nString title, String caseColor, String caseTitle, Integer priority, ActorRef assignee, AbstractUser user, List<Trigger> triggers, Map<String, Map<String, Boolean>> roles, Map<String, Map<String, Boolean>> userRefs, Map<String, Map<String, Boolean>> users, List<String> viewRoles, List<String> viewUserRefs, List<String> viewUsers, List<String> negativeViewRoles, List<String> negativeViewUsers, LocalDateTime startDate, LocalDateTime finishDate, String finishedBy, String transactionId, Boolean requiredFilled, LinkedHashSet<String> immediateDataFields, List<Field<?>> immediateData, String icon, AssignPolicy assignPolicy, DataFocusPolicy dataFocusPolicy, FinishPolicy finishPolicy, Map<EventType, I18nString> eventTitles, Map<String, Boolean> assignedUserPolicy, Map<String, Integer> consumedTokens, Map<String, String> tags) {
+        super(_id, processId, caseId, transitionId, layout, title, caseColor, caseTitle, priority, assignee, user, triggers, roles, userRefs, users, viewRoles, viewUserRefs, viewUsers, negativeViewRoles, negativeViewUsers, startDate, finishDate, finishedBy, transactionId, requiredFilled, immediateDataFields, immediateData, icon, assignPolicy, dataFocusPolicy, finishPolicy, eventTitles, assignedUserPolicy, consumedTokens, tags);
     }
 
     @Id