diff --git a/lucene/CHANGES.txt b/lucene/CHANGES.txt
index 425d6e2fb39..0935333ae1b 100644
--- a/lucene/CHANGES.txt
+++ b/lucene/CHANGES.txt
@@ -45,6 +45,10 @@ New Features
   applicable and supported when copying files from another FSDirectory in 
   Directory#copyFrom. (Simon Willnauer)
 
+* LUCENE-73012: IndexWriter methods that change the index now return a
+  long "sequence number" indicating the effective equivalent
+  single-threaded execution order (Mike McCandless)
+
 API Changes
 
 * LUCENE-7163: refactor GeoRect, Polygon, and GeoUtils tests to geo