diff --git a/src/limestone/log_entry.h b/src/limestone/log_entry.h
index 6e04c9f1..e5e991fe 100644
--- a/src/limestone/log_entry.h
+++ b/src/limestone/log_entry.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2022-2022 tsurugi project.
+ * Copyright 2022-2023 tsurugi project.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/test/limestone/log/log_entry_4_LevelDB_test.cpp b/test/limestone/log/log_entry_4_LevelDB_test.cpp
index 118cd1ab..a668ddc4 100644
--- a/test/limestone/log/log_entry_4_LevelDB_test.cpp
+++ b/test/limestone/log/log_entry_4_LevelDB_test.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2022-2022 tsurugi project.
+ * Copyright 2022-2023 tsurugi project.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/test/limestone/log/log_entry_test.cpp b/test/limestone/log/log_entry_test.cpp
index f40805c4..09db495e 100644
--- a/test/limestone/log/log_entry_test.cpp
+++ b/test/limestone/log/log_entry_test.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2022-2022 tsurugi project.
+ * Copyright 2022-2023 tsurugi project.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
diff --git a/test/limestone/log/log_entry_type_test.cpp b/test/limestone/log/log_entry_type_test.cpp
index 9b44d094..e3071866 100644
--- a/test/limestone/log/log_entry_type_test.cpp
+++ b/test/limestone/log/log_entry_type_test.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2022-2022 tsurugi project.
+ * Copyright 2022-2023 tsurugi project.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.