diff --git a/examples/client.c b/examples/client.c
index ae551e978..ea6094042 100644
--- a/examples/client.c
+++ b/examples/client.c
@@ -6,7 +6,7 @@
 
 #ifdef UA_ENABLE_SUBSCRIPTIONS
 static void
-handler_TheAnswerChanged(UA_UInt32 monId, UA_DataValue *value, void *context) {
+handler_TheAnswerChanged(UA_Client *client, UA_UInt32 monId, UA_DataValue *value, void *context) {
     printf("The Answer has changed!\n");
 }
 #endif
diff --git a/examples/client_subscription_loop.c b/examples/client_subscription_loop.c
index 763bdf05d..132f75bef 100644
--- a/examples/client_subscription_loop.c
+++ b/examples/client_subscription_loop.c
@@ -43,7 +43,7 @@ static void stopHandler(int sign) {
 }
 
 static void
-handler_currentTimeChanged(UA_UInt32 monId, UA_DataValue *value, void *context) {
+handler_currentTimeChanged(UA_Client *client, UA_UInt32 monId, UA_DataValue *value, void *context) {
     UA_LOG_INFO(logger, UA_LOGCATEGORY_USERLAND, "currentTime has changed!");
     if(UA_Variant_hasScalarType(&value->value, &UA_TYPES[UA_TYPES_DATETIME])) {
         UA_DateTime raw_date = *(UA_DateTime *) value->value.data;
diff --git a/include/ua_client_highlevel.h b/include/ua_client_highlevel.h
index 1823e993f..d989f5bfe 100644
--- a/include/ua_client_highlevel.h
+++ b/include/ua_client_highlevel.h
@@ -597,8 +597,8 @@ UA_Client_Subscriptions_manuallySendPublishRequest(UA_Client *client);
 
 /* Addition of monitored DataChanges */
 /* TODO for v0.4: Rename method to _DataChange. */
-typedef void (*UA_MonitoredItemHandlingFunction)(UA_UInt32 monId, UA_DataValue *value,
-                                                 void *context);
+typedef void (*UA_MonitoredItemHandlingFunction)(UA_Client *client, UA_UInt32 monId,
+                                                 UA_DataValue *value, void *context);
 
 UA_StatusCode UA_EXPORT
 UA_Client_Subscriptions_addMonitoredItems(UA_Client *client, const UA_UInt32 subscriptionId,
diff --git a/src/client/ua_client_highlevel_subscriptions.c b/src/client/ua_client_highlevel_subscriptions.c
index 399da77ca..97dcf25d9 100644
--- a/src/client/ua_client_highlevel_subscriptions.c
+++ b/src/client/ua_client_highlevel_subscriptions.c
@@ -424,7 +424,8 @@ UA_Client_processPublishResponse(UA_Client *client, UA_PublishRequest *request,
                     continue;
                 }
 
-                mon->handler.dataChangeHandler(mon->monitoredItemId, &mitemNot->value, mon->handlerContext);
+                mon->handler.dataChangeHandler(client, mon->monitoredItemId,
+                                               &mitemNot->value, mon->handlerContext);
             }
             continue;
         }
diff --git a/tests/client/check_client_subscriptions.c b/tests/client/check_client_subscriptions.c
index c5edda8c5..7df9a2a2a 100644
--- a/tests/client/check_client_subscriptions.c
+++ b/tests/client/check_client_subscriptions.c
@@ -53,7 +53,7 @@ static void teardown(void) {
 UA_Boolean notificationReceived;
 UA_UInt32 countNotificationReceived = 0;
 
-static void monitoredItemHandler(UA_UInt32 monId, UA_DataValue *value, void *context) {
+static void monitoredItemHandler(UA_Client *client, UA_UInt32 monId, UA_DataValue *value, void *context) {
     notificationReceived = true;
     countNotificationReceived++;
 }
diff --git a/tests/fuzz/corpus_generator.c b/tests/fuzz/corpus_generator.c
index a411478fd..8c1672cb4 100644
--- a/tests/fuzz/corpus_generator.c
+++ b/tests/fuzz/corpus_generator.c
@@ -360,7 +360,7 @@ translateBrowsePathsToNodeIdsRequest(UA_Client *client) {
 
 
 static void
-monitoredItemHandler(UA_UInt32 monId, UA_DataValue *value, void *context) {
+monitoredItemHandler(UA_Client *client, UA_UInt32 monId, UA_DataValue *value, void *context) {
 
 }