diff --git a/subprojects/gstreamer/gst/gstevent.c b/subprojects/gstreamer/gst/gstevent.c
index 6ab77b3d85..0bd4ac06e6 100644
--- a/subprojects/gstreamer/gst/gstevent.c
+++ b/subprojects/gstreamer/gst/gstevent.c
@@ -1979,7 +1979,7 @@ gst_event_new_stream_collection (GstStreamCollection * collection)
 /**
  * gst_event_parse_stream_collection:
  * @event: a stream-collection event
- * @collection: (out) (optional): pointer to store the collection
+ * @collection: (out) (optional) (transfer full): pointer to store the collection.
  *
  * Retrieve new #GstStreamCollection from STREAM_COLLECTION event @event.
  *