diff --git a/docs/ipc b/docs/ipc
index ff60dbd1..17397548 100644
--- a/docs/ipc
+++ b/docs/ipc
@@ -644,11 +644,15 @@ if ($is_event) {
 
 This event consists of a single serialized map containing a property
 +change (string)+ which indicates the type of the change ("focus", "init",
-"empty", "urgent").  Additionally, when the change is "focus", an +old
-(object)+ and a +current (object)+ properties will be present with the
-previous and current workspace respectively.  When the first switch
-occurs (when i3 focuses the workspace visible at the beginning) there is
-no previous workspace, and the +old+ property will be set to +null+.
+"empty", "urgent").
+
+Moreover, when the change is "focus", an +old (object)+ and a +current
+(object)+ properties will be present with the previous and current
+workspace respectively.  When the first switch occurs (when i3 focuses
+the workspace visible at the beginning) there is no previous
+workspace, and the +old+ property will be set to +null+.  Also note
+that if the previous is empty it will get destroyed when switching,
+but will still be present in the "old" property.
 
 *Example:*
 ---------------------