diff --git a/WHATS_NEW b/WHATS_NEW
index 6a0a0dcde..46f66b0f7 100644
--- a/WHATS_NEW
+++ b/WHATS_NEW
@@ -1,5 +1,6 @@
 Version 2.02.178 - 
 =====================================
+  Fix compatibility size test of extended external origin.
   Add external_origin visiting in for_each_sub_lv().
   Ensure cluster commands drop their device cache before locking VG.
   Do not report LV as remotely active when it's locally exclusive in cluster.
diff --git a/lib/metadata/lv_manip.c b/lib/metadata/lv_manip.c
index 12f444b7b..28f00abd9 100644
--- a/lib/metadata/lv_manip.c
+++ b/lib/metadata/lv_manip.c
@@ -5334,7 +5334,7 @@ static int _lvresize_check_type(const struct logical_volume *lv,
 
 		/* Validate thin target supports bigger size of thin volume then external origin */
 		if (lv_is_thin_volume(lv) && first_seg(lv)->external_lv &&
-		    (lv->size > first_seg(lv)->external_lv->size) &&
+		    (lp->extents > first_seg(lv)->external_lv->le_count) &&
 		    !thin_pool_feature_supported(first_seg(lv)->pool_lv, THIN_FEATURE_EXTERNAL_ORIGIN_EXTEND)) {
 			log_error("Thin target does not support external origin smaller then thin volume.");
 			return 0;