diff --git a/lucene/CHANGES.txt b/lucene/CHANGES.txt
index 6e7690119d3..f6ee2edbde8 100644
--- a/lucene/CHANGES.txt
+++ b/lucene/CHANGES.txt
@@ -250,6 +250,8 @@ API Changes
 
 * GITHUB#13281: Mark COSINE VectorSimilarityFunction as deprecated. (Pulkit Gupta)
 
+* GITHUB#13469: Expose FlatVectorsFormat as a first-class format; can be configured using a custom Codec. (Michael Sokolov) 
+
 New Features
 ---------------------
 (No changes)