diff --git a/libcutils/include/cutils/qtaguid.h b/libcutils/include/cutils/qtaguid.h
index f8550fda8..803fe0d9a 100644
--- a/libcutils/include/cutils/qtaguid.h
+++ b/libcutils/include/cutils/qtaguid.h
@@ -26,13 +26,15 @@ extern "C" {
 #endif
 
 /*
- * Set tags (and owning UIDs) for network sockets.
-*/
+ * Set tags (and owning UIDs) for network sockets. The socket must be untagged
+ * by calling qtaguid_untagSocket() before closing it, otherwise the qtaguid
+ * module will keep a reference to it even after close.
+ */
 extern int qtaguid_tagSocket(int sockfd, int tag, uid_t uid);
 
 /*
  * Untag a network socket before closing.
-*/
+ */
 extern int qtaguid_untagSocket(int sockfd);
 
 /*