diff --git a/docs/labs.md b/docs/labs.md
index efe1fc13bc..0f88d898c0 100644
--- a/docs/labs.md
+++ b/docs/labs.md
@@ -93,3 +93,8 @@ tab as the single source of truth just yet.
 
 This adds a presence indicator in the room list next to DM rooms where the other
 person is online.
+
+## Show padlocks on invite only rooms (`feature_invite_only_padlocks`)
+
+This adds padlocks to room list tiles and room header for invite only rooms.
+This feature flag (unlike most) is enabled by default.