diff --git a/COPYRIGHT b/COPYRIGHT
index 7693c589..2551eb8a 100644
--- a/COPYRIGHT
+++ b/COPYRIGHT
@@ -1,6 +1,6 @@
-Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
 
-Portions Copyright (c) 1996-2021, PostgreSQL Global Development Group
+Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
 Portions Copyright (c) 1994, The Regents of the University of California
 
 Redistribution and use in source and binary forms, with or without
diff --git a/backup.c b/backup.c
index d3430d51..17ce2a64 100644
--- a/backup.c
+++ b/backup.c
@@ -2,7 +2,7 @@
  *
  * backup.c: backup DB cluster, archived WAL, serverlog.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/catalog.c b/catalog.c
index 456976d8..9cf7fd84 100644
--- a/catalog.c
+++ b/catalog.c
@@ -2,7 +2,7 @@
  *
  * catalog.c: backup catalog operation
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/data.c b/data.c
index 6ee2ffd4..9c10c919 100644
--- a/data.c
+++ b/data.c
@@ -3,7 +3,7 @@
  * data.c: utilities for backing up and restoring database files along with
  * the support for compression/decompression of individual data file pages
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/delete.c b/delete.c
index d62ba692..6ba8767a 100644
--- a/delete.c
+++ b/delete.c
@@ -2,7 +2,7 @@
  *
  * delete.c: delete backup files.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/dir.c b/dir.c
index 0ca4c460..7d9ceba4 100644
--- a/dir.c
+++ b/dir.c
@@ -2,7 +2,7 @@
  *
  * dir.c: directory operation utility.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/docs/index-ja.html b/docs/index-ja.html
index b6a5d16c..7a277095 100755
--- a/docs/index-ja.html
+++ b/docs/index-ja.html
@@ -1474,7 +1474,7 @@ <h1 id="seealso">関連項目</h2>
 
 <hr />
 
-<p class="footer">Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION</p>
+<p class="footer">Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION</p>
 
 </body>
-</html>
+</html>
\ No newline at end of file
diff --git a/docs/index.html b/docs/index.html
index b79dd7ff..c27ad071 100755
--- a/docs/index.html
+++ b/docs/index.html
@@ -1460,7 +1460,7 @@ <h1 id="seealso">See Also</h2>
 
 <hr />
 
-<p class="footer">Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION</p>
+<p class="footer">Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION</p>
 
 </body>
-</html>
+</html>
\ No newline at end of file
diff --git a/idxpagehdr.h b/idxpagehdr.h
index 63b31f55..bdba7344 100644
--- a/idxpagehdr.h
+++ b/idxpagehdr.h
@@ -13,7 +13,7 @@
  * file!!!  Although, incompatible changes to the definitions in this file
  * will be rare.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/init.c b/init.c
index 93c1f31e..da8a47a3 100644
--- a/init.c
+++ b/init.c
@@ -2,7 +2,7 @@
  *
  * init.c: manage backup catalog.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/parray.c b/parray.c
index 1123d75e..b6dc23c7 100644
--- a/parray.c
+++ b/parray.c
@@ -2,7 +2,7 @@
  *
  * parray.c: pointer array collection.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/parray.h b/parray.h
index 8b6c8844..2a6a1fea 100644
--- a/parray.h
+++ b/parray.h
@@ -2,7 +2,7 @@
  *
  * parray.h: pointer array collection.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/pg_rman.c b/pg_rman.c
index fa7b6010..058b4c67 100644
--- a/pg_rman.c
+++ b/pg_rman.c
@@ -2,7 +2,7 @@
  *
  * pg_rman.c: Backup/Recovery manager for PostgreSQL.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/pg_rman.h b/pg_rman.h
index 2bc24d6d..f618db38 100644
--- a/pg_rman.h
+++ b/pg_rman.h
@@ -2,7 +2,7 @@
  *
  * pg_rman.h: Backup/Recovery manager for PostgreSQL.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/pgut/pgut-port.c b/pgut/pgut-port.c
index d2ccba3b..369ca083 100644
--- a/pgut/pgut-port.c
+++ b/pgut/pgut-port.c
@@ -2,7 +2,7 @@
  *
  * pgut-port.c
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/pgut/pgut-port.h b/pgut/pgut-port.h
index 1e089a70..d148dae9 100644
--- a/pgut/pgut-port.h
+++ b/pgut/pgut-port.h
@@ -2,7 +2,7 @@
  *
  * pgut-port.h
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/pgut/pgut.c b/pgut/pgut.c
index 3ab66b1d..8e2e7a23 100644
--- a/pgut/pgut.c
+++ b/pgut/pgut.c
@@ -2,7 +2,7 @@
  *
  * pgut.c
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/pgut/pgut.h b/pgut/pgut.h
index 7fc6cdc1..de7d7ae4 100644
--- a/pgut/pgut.h
+++ b/pgut/pgut.h
@@ -2,7 +2,7 @@
  *
  * pgut.h
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/restore.c b/restore.c
index 58a45806..7c64f245 100644
--- a/restore.c
+++ b/restore.c
@@ -2,7 +2,7 @@
  *
  * restore.c: restore DB cluster and archived WAL.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/script/snapshot_script_lvm.sh b/script/snapshot_script_lvm.sh
index 7797ec1c..93e16cd9 100644
--- a/script/snapshot_script_lvm.sh
+++ b/script/snapshot_script_lvm.sh
@@ -1,6 +1,6 @@
 #!/bin/sh
 #############################################################################
-#  Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+#  Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
 #############################################################################
 
 CMD_SUDO="/usr/bin/sudo"
diff --git a/show.c b/show.c
index 9f10cfae..15e2831e 100644
--- a/show.c
+++ b/show.c
@@ -2,7 +2,7 @@
  *
  * show.c: show backup catalog.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/util.c b/util.c
index bbccc718..6a0c6c4b 100644
--- a/util.c
+++ b/util.c
@@ -2,7 +2,7 @@
  *
  * util.c: log messages to log file or stderr, and misc code.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/validate.c b/validate.c
index 0d8df757..968ee0ef 100644
--- a/validate.c
+++ b/validate.c
@@ -2,7 +2,7 @@
  *
  * validate.c: validate backup files.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */
diff --git a/xlog.c b/xlog.c
index 1d0af10a..6dd574f1 100644
--- a/xlog.c
+++ b/xlog.c
@@ -2,7 +2,7 @@
  *
  * xlog.c: Parse WAL files.
  *
- * Copyright (c) 2009-2022, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
+ * Copyright (c) 2009-2023, NIPPON TELEGRAPH AND TELEPHONE CORPORATION
  *
  *-------------------------------------------------------------------------
  */