diff --git a/src/main/java/org/gcube/portlets/widgets/workspacesharingwidget/server/WorkspaceSharingServiceImpl.java b/src/main/java/org/gcube/portlets/widgets/workspacesharingwidget/server/WorkspaceSharingServiceImpl.java
index e8d1fb3..0901d3e 100644
--- a/src/main/java/org/gcube/portlets/widgets/workspacesharingwidget/server/WorkspaceSharingServiceImpl.java
+++ b/src/main/java/org/gcube/portlets/widgets/workspacesharingwidget/server/WorkspaceSharingServiceImpl.java
@@ -833,15 +833,46 @@ public class WorkspaceSharingServiceImpl extends RemoteServiceServlet implements
 							}
 						}
 					}
-
-					logger.debug("Update ACL for add Administrators");
+					
+					logger.debug("Share with new Administrators");
+					HashSet<String> shareUsers = new HashSet<>();
+					boolean alreadyShared;
 					for (String user : listContactLogins) {
 						if (currentUser.compareTo(user) != 0) {
-							folderContainer = folderContainer.changeAcls(user, AccessType.ADMINISTRATOR);
+							alreadyShared = false;
+							for (ACL acl : acls) {
+								if (user.compareTo(acl.getPricipal()) == 0) {
+									alreadyShared = true;
+									break;
+								}
+							}
+							if (!alreadyShared) {
+								shareUsers.add(user);
+							}
+						}
+					}
+					
+					logger.debug("Update ACL for add Administrators");
+					if (shareUsers.isEmpty()) {
+						for (String user : listContactLogins) {
+							if (currentUser.compareTo(user) != 0) {
+								folderContainer = folderContainer.changeAcls(user, AccessType.ADMINISTRATOR);
+							}
+						}
+					} else {
+						folderContainer = folderContainer.share(shareUsers, AccessType.ADMINISTRATOR);
+						HashSet<String> aclUpdateUsers = new HashSet<>(listContactLogins);
+						aclUpdateUsers.removeAll(shareUsers);
+						for (String user : aclUpdateUsers) {
+							if (currentUser.compareTo(user) != 0) {
+								folderContainer = folderContainer.changeAcls(user, AccessType.ADMINISTRATOR);
+							}
 						}
 					}
-					logger.debug("Update Administrators done");
 
+				
+					
+					logger.debug("Update Administrators done");
 					if (!alreadyAdministrators.isEmpty()) {
 						alreadyAdministrators.removeAll(listContactLogins);
 						if (!alreadyAdministrators.isEmpty()) {