diff --git a/unified-runtime/include/ur_api.h b/unified-runtime/include/ur_api.h
index a65393fe0e155..dcf05b2b066c7 100644
--- a/unified-runtime/include/ur_api.h
+++ b/unified-runtime/include/ur_api.h
@@ -9233,6 +9233,9 @@ typedef struct ur_usm_pool_buffer_desc_t {
 ///         + `NULL == ppMem`
 ///     - ::UR_RESULT_ERROR_OUT_OF_RESOURCES
 ///     - ::UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+///         + `phEventWaitList == NULL && numEventsInWaitList > 0`
+///         + `phEventWaitList != NULL && numEventsInWaitList == 0`
+///         + If event objects in phEventWaitList are not valid events.
 UR_APIEXPORT ur_result_t UR_APICALL urEnqueueUSMDeviceAllocExp(
     /// [in] handle of the queue object
     ur_queue_handle_t hQueue,
@@ -9271,6 +9274,9 @@ UR_APIEXPORT ur_result_t UR_APICALL urEnqueueUSMDeviceAllocExp(
 ///         + `NULL == ppMem`
 ///     - ::UR_RESULT_ERROR_OUT_OF_RESOURCES
 ///     - ::UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+///         + `phEventWaitList == NULL && numEventsInWaitList > 0`
+///         + `phEventWaitList != NULL && numEventsInWaitList == 0`
+///         + If event objects in phEventWaitList are not valid events.
 UR_APIEXPORT ur_result_t UR_APICALL urEnqueueUSMSharedAllocExp(
     /// [in] handle of the queue object
     ur_queue_handle_t hQueue,
@@ -9310,6 +9316,9 @@ UR_APIEXPORT ur_result_t UR_APICALL urEnqueueUSMSharedAllocExp(
 ///     - ::UR_RESULT_ERROR_OUT_OF_RESOURCES
 ///     - ::UR_RESULT_ERROR_OUT_OF_HOST_MEMORY
 ///     - ::UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+///         + `phEventWaitList == NULL && numEventsInWaitList > 0`
+///         + `phEventWaitList != NULL && numEventsInWaitList == 0`
+///         + If event objects in phEventWaitList are not valid events.
 UR_APIEXPORT ur_result_t UR_APICALL urEnqueueUSMHostAllocExp(
     /// [in] handle of the queue object
     ur_queue_handle_t hQueue,
@@ -9346,6 +9355,9 @@ UR_APIEXPORT ur_result_t UR_APICALL urEnqueueUSMHostAllocExp(
 ///     - ::UR_RESULT_ERROR_OUT_OF_RESOURCES
 ///     - ::UR_RESULT_ERROR_OUT_OF_HOST_MEMORY
 ///     - ::UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+///         + `phEventWaitList == NULL && numEventsInWaitList > 0`
+///         + `phEventWaitList != NULL && numEventsInWaitList == 0`
+///         + If event objects in phEventWaitList are not valid events.
 UR_APIEXPORT ur_result_t UR_APICALL urEnqueueUSMFreeExp(
     /// [in] handle of the queue object
     ur_queue_handle_t hQueue,
diff --git a/unified-runtime/scripts/core/exp-async-alloc.yml b/unified-runtime/scripts/core/exp-async-alloc.yml
index 08887d060e53a..47f759dcdd79c 100644
--- a/unified-runtime/scripts/core/exp-async-alloc.yml
+++ b/unified-runtime/scripts/core/exp-async-alloc.yml
@@ -173,7 +173,10 @@ returns:
     - $X_RESULT_ERROR_OUT_OF_RESOURCES
     - $X_RESULT_ERROR_INVALID_NULL_HANDLE
     - $X_RESULT_ERROR_INVALID_NULL_POINTER
-    - $X_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+    - $X_RESULT_ERROR_INVALID_EVENT_WAIT_LIST:
+        - "`phEventWaitList == NULL && numEventsInWaitList > 0`"
+        - "`phEventWaitList != NULL && numEventsInWaitList == 0`"
+        - "If event objects in phEventWaitList are not valid events."
 
 --- #--------------------------------------------------------------------------
 type: function
@@ -211,7 +214,10 @@ returns:
     - $X_RESULT_ERROR_OUT_OF_RESOURCES
     - $X_RESULT_ERROR_INVALID_NULL_HANDLE
     - $X_RESULT_ERROR_INVALID_NULL_POINTER
-    - $X_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+    - $X_RESULT_ERROR_INVALID_EVENT_WAIT_LIST:
+        - "`phEventWaitList == NULL && numEventsInWaitList > 0`"
+        - "`phEventWaitList != NULL && numEventsInWaitList == 0`"
+        - "If event objects in phEventWaitList are not valid events."
 
 --- #--------------------------------------------------------------------------
 type: function
@@ -250,7 +256,10 @@ returns:
     - $X_RESULT_ERROR_OUT_OF_HOST_MEMORY
     - $X_RESULT_ERROR_INVALID_NULL_HANDLE
     - $X_RESULT_ERROR_INVALID_NULL_POINTER
-    - $X_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+    - $X_RESULT_ERROR_INVALID_EVENT_WAIT_LIST:
+        - "`phEventWaitList == NULL && numEventsInWaitList > 0`"
+        - "`phEventWaitList != NULL && numEventsInWaitList == 0`"
+        - "If event objects in phEventWaitList are not valid events."
 
 --- #--------------------------------------------------------------------------
 type: function
@@ -283,7 +292,10 @@ returns:
     - $X_RESULT_ERROR_OUT_OF_HOST_MEMORY
     - $X_RESULT_ERROR_INVALID_NULL_HANDLE
     - $X_RESULT_ERROR_INVALID_NULL_POINTER
-    - $X_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+    - $X_RESULT_ERROR_INVALID_EVENT_WAIT_LIST:
+        - "`phEventWaitList == NULL && numEventsInWaitList > 0`"
+        - "`phEventWaitList != NULL && numEventsInWaitList == 0`"
+        - "If event objects in phEventWaitList are not valid events."
 
 --- #--------------------------------------------------------------------------
 type: function
diff --git a/unified-runtime/source/loader/layers/validation/ur_valddi.cpp b/unified-runtime/source/loader/layers/validation/ur_valddi.cpp
index 87023c800e234..bb4f35e269613 100644
--- a/unified-runtime/source/loader/layers/validation/ur_valddi.cpp
+++ b/unified-runtime/source/loader/layers/validation/ur_valddi.cpp
@@ -6804,6 +6804,12 @@ __urdlllocal ur_result_t UR_APICALL urEnqueueUSMDeviceAllocExp(
         UR_EXP_ASYNC_USM_ALLOC_FLAGS_MASK & pProperties->flags)
       return UR_RESULT_ERROR_INVALID_ENUMERATION;
 
+    if (phEventWaitList == NULL && numEventsInWaitList > 0)
+      return UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST;
+
+    if (phEventWaitList != NULL && numEventsInWaitList == 0)
+      return UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST;
+
     if (phEventWaitList != NULL && numEventsInWaitList > 0) {
       for (uint32_t i = 0; i < numEventsInWaitList; ++i) {
         if (phEventWaitList[i] == NULL) {
@@ -6875,6 +6881,12 @@ __urdlllocal ur_result_t UR_APICALL urEnqueueUSMSharedAllocExp(
         UR_EXP_ASYNC_USM_ALLOC_FLAGS_MASK & pProperties->flags)
       return UR_RESULT_ERROR_INVALID_ENUMERATION;
 
+    if (phEventWaitList == NULL && numEventsInWaitList > 0)
+      return UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST;
+
+    if (phEventWaitList != NULL && numEventsInWaitList == 0)
+      return UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST;
+
     if (phEventWaitList != NULL && numEventsInWaitList > 0) {
       for (uint32_t i = 0; i < numEventsInWaitList; ++i) {
         if (phEventWaitList[i] == NULL) {
@@ -6946,6 +6958,12 @@ __urdlllocal ur_result_t UR_APICALL urEnqueueUSMHostAllocExp(
         UR_EXP_ASYNC_USM_ALLOC_FLAGS_MASK & pProperties->flags)
       return UR_RESULT_ERROR_INVALID_ENUMERATION;
 
+    if (phEventWaitList == NULL && numEventsInWaitList > 0)
+      return UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST;
+
+    if (phEventWaitList != NULL && numEventsInWaitList == 0)
+      return UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST;
+
     if (phEventWaitList != NULL && numEventsInWaitList > 0) {
       for (uint32_t i = 0; i < numEventsInWaitList; ++i) {
         if (phEventWaitList[i] == NULL) {
@@ -7008,6 +7026,12 @@ __urdlllocal ur_result_t UR_APICALL urEnqueueUSMFreeExp(
     if (NULL == hQueue)
       return UR_RESULT_ERROR_INVALID_NULL_HANDLE;
 
+    if (phEventWaitList == NULL && numEventsInWaitList > 0)
+      return UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST;
+
+    if (phEventWaitList != NULL && numEventsInWaitList == 0)
+      return UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST;
+
     if (phEventWaitList != NULL && numEventsInWaitList > 0) {
       for (uint32_t i = 0; i < numEventsInWaitList; ++i) {
         if (phEventWaitList[i] == NULL) {
diff --git a/unified-runtime/source/loader/ur_libapi.cpp b/unified-runtime/source/loader/ur_libapi.cpp
index bd02b6fa90222..41d52b781fdf5 100644
--- a/unified-runtime/source/loader/ur_libapi.cpp
+++ b/unified-runtime/source/loader/ur_libapi.cpp
@@ -6790,6 +6790,9 @@ ur_result_t UR_APICALL urEnqueueWriteHostPipe(
 ///         + `NULL == ppMem`
 ///     - ::UR_RESULT_ERROR_OUT_OF_RESOURCES
 ///     - ::UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+///         + `phEventWaitList == NULL && numEventsInWaitList > 0`
+///         + `phEventWaitList != NULL && numEventsInWaitList == 0`
+///         + If event objects in phEventWaitList are not valid events.
 ur_result_t UR_APICALL urEnqueueUSMDeviceAllocExp(
     /// [in] handle of the queue object
     ur_queue_handle_t hQueue,
@@ -6839,6 +6842,9 @@ ur_result_t UR_APICALL urEnqueueUSMDeviceAllocExp(
 ///         + `NULL == ppMem`
 ///     - ::UR_RESULT_ERROR_OUT_OF_RESOURCES
 ///     - ::UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+///         + `phEventWaitList == NULL && numEventsInWaitList > 0`
+///         + `phEventWaitList != NULL && numEventsInWaitList == 0`
+///         + If event objects in phEventWaitList are not valid events.
 ur_result_t UR_APICALL urEnqueueUSMSharedAllocExp(
     /// [in] handle of the queue object
     ur_queue_handle_t hQueue,
@@ -6889,6 +6895,9 @@ ur_result_t UR_APICALL urEnqueueUSMSharedAllocExp(
 ///     - ::UR_RESULT_ERROR_OUT_OF_RESOURCES
 ///     - ::UR_RESULT_ERROR_OUT_OF_HOST_MEMORY
 ///     - ::UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+///         + `phEventWaitList == NULL && numEventsInWaitList > 0`
+///         + `phEventWaitList != NULL && numEventsInWaitList == 0`
+///         + If event objects in phEventWaitList are not valid events.
 ur_result_t UR_APICALL urEnqueueUSMHostAllocExp(
     /// [in] handle of the queue object
     ur_queue_handle_t hQueue,
@@ -6936,6 +6945,9 @@ ur_result_t UR_APICALL urEnqueueUSMHostAllocExp(
 ///     - ::UR_RESULT_ERROR_OUT_OF_RESOURCES
 ///     - ::UR_RESULT_ERROR_OUT_OF_HOST_MEMORY
 ///     - ::UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+///         + `phEventWaitList == NULL && numEventsInWaitList > 0`
+///         + `phEventWaitList != NULL && numEventsInWaitList == 0`
+///         + If event objects in phEventWaitList are not valid events.
 ur_result_t UR_APICALL urEnqueueUSMFreeExp(
     /// [in] handle of the queue object
     ur_queue_handle_t hQueue,
diff --git a/unified-runtime/source/ur_api.cpp b/unified-runtime/source/ur_api.cpp
index 602aad1104605..5c648d51a91c7 100644
--- a/unified-runtime/source/ur_api.cpp
+++ b/unified-runtime/source/ur_api.cpp
@@ -5967,6 +5967,9 @@ ur_result_t UR_APICALL urEnqueueWriteHostPipe(
 ///         + `NULL == ppMem`
 ///     - ::UR_RESULT_ERROR_OUT_OF_RESOURCES
 ///     - ::UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+///         + `phEventWaitList == NULL && numEventsInWaitList > 0`
+///         + `phEventWaitList != NULL && numEventsInWaitList == 0`
+///         + If event objects in phEventWaitList are not valid events.
 ur_result_t UR_APICALL urEnqueueUSMDeviceAllocExp(
     /// [in] handle of the queue object
     ur_queue_handle_t hQueue,
@@ -6008,6 +6011,9 @@ ur_result_t UR_APICALL urEnqueueUSMDeviceAllocExp(
 ///         + `NULL == ppMem`
 ///     - ::UR_RESULT_ERROR_OUT_OF_RESOURCES
 ///     - ::UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+///         + `phEventWaitList == NULL && numEventsInWaitList > 0`
+///         + `phEventWaitList != NULL && numEventsInWaitList == 0`
+///         + If event objects in phEventWaitList are not valid events.
 ur_result_t UR_APICALL urEnqueueUSMSharedAllocExp(
     /// [in] handle of the queue object
     ur_queue_handle_t hQueue,
@@ -6050,6 +6056,9 @@ ur_result_t UR_APICALL urEnqueueUSMSharedAllocExp(
 ///     - ::UR_RESULT_ERROR_OUT_OF_RESOURCES
 ///     - ::UR_RESULT_ERROR_OUT_OF_HOST_MEMORY
 ///     - ::UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+///         + `phEventWaitList == NULL && numEventsInWaitList > 0`
+///         + `phEventWaitList != NULL && numEventsInWaitList == 0`
+///         + If event objects in phEventWaitList are not valid events.
 ur_result_t UR_APICALL urEnqueueUSMHostAllocExp(
     /// [in] handle of the queue object
     ur_queue_handle_t hQueue,
@@ -6089,6 +6098,9 @@ ur_result_t UR_APICALL urEnqueueUSMHostAllocExp(
 ///     - ::UR_RESULT_ERROR_OUT_OF_RESOURCES
 ///     - ::UR_RESULT_ERROR_OUT_OF_HOST_MEMORY
 ///     - ::UR_RESULT_ERROR_INVALID_EVENT_WAIT_LIST
+///         + `phEventWaitList == NULL && numEventsInWaitList > 0`
+///         + `phEventWaitList != NULL && numEventsInWaitList == 0`
+///         + If event objects in phEventWaitList are not valid events.
 ur_result_t UR_APICALL urEnqueueUSMFreeExp(
     /// [in] handle of the queue object
     ur_queue_handle_t hQueue,