diff --git a/libavformat/matroska.h b/libavformat/matroska.h
index 98b2165fda..a683bc70b3 100644
--- a/libavformat/matroska.h
+++ b/libavformat/matroska.h
@@ -64,6 +64,7 @@
 #define MATROSKA_ID_WRITINGAPP 0x5741
 #define MATROSKA_ID_MUXINGAPP  0x4D80
 #define MATROSKA_ID_DATEUTC    0x4461
+#define MATROSKA_ID_SEGMENTUID 0x73A4
 
 /* ID in the tracks master */
 #define MATROSKA_ID_TRACKENTRY 0xAE