diff --git a/css/properties.json b/css/properties.json
index 7e0e0fff..3662ee8e 100644
--- a/css/properties.json
+++ b/css/properties.json
@@ -1864,7 +1864,7 @@
     "appliesto": "allElements",
     "computed": "asSpecified",
     "order": "uniqueOrder",
-    "status": "experimental",
+    "status": "standard",
     "mdn_url": "https://developer.mozilla.org/docs/Web/CSS/animation-composition"
   },
   "animation-delay": {
diff --git a/css/syntaxes.json b/css/syntaxes.json
index 68f68c85..4a0ce22e 100644
--- a/css/syntaxes.json
+++ b/css/syntaxes.json
@@ -782,6 +782,9 @@
   "single-animation": {
     "syntax": "<'animation-duration'> || <easing-function> || <'animation-delay'> || <single-animation-iteration-count> || <single-animation-direction> || <single-animation-fill-mode> || <single-animation-play-state> || [ none | <keyframes-name> ] || <single-animation-timeline>"
   },
+  "single-animation-composition": {
+    "syntax": "replace | add | accumulate"
+  },
   "single-animation-direction": {
     "syntax": "normal | reverse | alternate | alternate-reverse"
   },