diff --git a/test/limestone/log/log_channel_test.cpp b/test/limestone/log/log_channel_test.cpp
index b94fa162..2e0a2cf0 100644
--- a/test/limestone/log/log_channel_test.cpp
+++ b/test/limestone/log/log_channel_test.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2022-2022 tsurugi project.
+ * Copyright 2022-2023 Project Tsurugi.
  *
  * 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 a668ddc4..fb164cb0 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 2022-2023 tsurugi project.
+ * Copyright 2022-2023 Project Tsurugi.
  *
  * 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 09db495e..5481527d 100644
--- a/test/limestone/log/log_entry_test.cpp
+++ b/test/limestone/log/log_entry_test.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2022-2023 tsurugi project.
+ * Copyright 2022-2023 Project Tsurugi.
  *
  * 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 e3071866..2594c2d9 100644
--- a/test/limestone/log/log_entry_type_test.cpp
+++ b/test/limestone/log/log_entry_type_test.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2022-2023 tsurugi project.
+ * Copyright 2022-2023 Project Tsurugi.
  *
  * 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/main.cpp b/test/main.cpp
index 82addfa5..e76d49ad 100644
--- a/test/main.cpp
+++ b/test/main.cpp
@@ -1,5 +1,5 @@
 /*
- * Copyright 2022-2022 tsurugi project.
+ * Copyright 2022-2023 Project Tsurugi.
  *
  * 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/test_root.h b/test/test_root.h
index e101ff0e..4d450b43 100644
--- a/test/test_root.h
+++ b/test/test_root.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2019-2019 tsurugi project.
+ * Copyright 2019-2023 Project Tsurugi.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.