diff --git a/ol-base.json b/ol-base.json
index a27b962f70..142140ce81 100644
--- a/ol-base.json
+++ b/ol-base.json
@@ -21,6 +21,7 @@
 
   "externs": [
     "externs/bingmaps.js",
+    "externs/tilejson.js",
     "externs/webgl-debug.js"
   ],