diff --git a/less/tooltip.less b/less/tooltip.less
index ecab304b82..8f7fcbebc1 100644
--- a/less/tooltip.less
+++ b/less/tooltip.less
@@ -39,6 +39,7 @@
   border-color: transparent;
   border-style: solid;
 }
+// Note: Deprecated .top-left, .top-right, .bottom-left, and .bottom-right as of v3.3.1
 .tooltip {
   &.top .tooltip-arrow {
     bottom: 0;