diff --git a/package.json b/package.json
index d1423b0d48..5a00c16bf6 100644
--- a/package.json
+++ b/package.json
@@ -74,6 +74,7 @@
     "types/**/*.d.ts",
     "index.html",
     "polymer-*.js",
-    "manifest.json"
-  ]
+    "manifest.json",
+    "interfaces.d.ts"
+]
 }