diff --git a/README.md b/README.md
index 2b83ca7..0b145e1 100644
--- a/README.md
+++ b/README.md
@@ -95,8 +95,8 @@ sequenceDiagram
 ## ライセンス
 
 ```
-Copyright 2022-2023, Hiroshi Yoshida (Original Author)
-Copyright 2022-2023, Shiguredo Inc.
+Copyright 2022-2024, Hiroshi Yoshida (Original Author)
+Copyright 2022-2024, Shiguredo Inc.
 
 Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.