diff --git a/package.json b/package.json
index 6c989bf1..05f0a6a5 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@xpadev-net/niconicomments",
-  "version": "0.2.23",
+  "version": "0.2.24",
   "description": "NiconiComments is a comment drawing library that is somewhat compatible with the official Nico Nico Douga player.",
   "main": "dist/bundle.js",
   "types": "dist/dts/types.d.ts",
diff --git a/src/typeGuard.ts b/src/typeGuard.ts
index b7b36709..aff98a73 100644
--- a/src/typeGuard.ts
+++ b/src/typeGuard.ts
@@ -62,14 +62,7 @@ const typeGuard = {
     },
     apiChat: (i: unknown): i is apiChat =>
       typeof i === "object" &&
-      typeVerify(i as apiChat, [
-        "content",
-        "date",
-        "date_usec",
-        "no",
-        "thread",
-        "vpos",
-      ]),
+      typeVerify(i as apiChat, ["content", "date", "no", "thread", "vpos"]),
     apiGlobalNumRes: (i: unknown): i is apiGlobalNumRes =>
       typeVerify(i, ["num_res", "thread"]),
     apiLeaf: (i: unknown): i is apiLeaf => typeVerify(i, ["count", "thread"]),