diff --git a/driver/main.c b/driver/main.c
index 3efee7f4f..d3eba6bb0 100644
--- a/driver/main.c
+++ b/driver/main.c
@@ -1,5 +1,5 @@
 const char COPYRIGHT[] =
-  "Copyright (c) 2000-2021 Stephen Williams (steve@icarus.com)";
+  "Copyright (c) 2000-2023 Stephen Williams (steve@icarus.com)";
 /*
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
diff --git a/ivlpp/main.c b/ivlpp/main.c
index 1a3e3b03b..2c67828ab 100644
--- a/ivlpp/main.c
+++ b/ivlpp/main.c
@@ -1,5 +1,5 @@
 const char COPYRIGHT[] =
-  "Copyright (c) 1999-2021 Stephen Williams (steve@icarus.com)";
+  "Copyright (c) 1999-2023 Stephen Williams (steve@icarus.com)";
 /*
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
diff --git a/main.cc b/main.cc
index 187ab9611..8b93f1c62 100644
--- a/main.cc
+++ b/main.cc
@@ -1,5 +1,5 @@
 const char COPYRIGHT[] =
-  "Copyright (c) 1998-2022 Stephen Williams (steve@icarus.com)";
+  "Copyright (c) 1998-2023 Stephen Williams (steve@icarus.com)";
 /*
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
diff --git a/tgt-blif/blif.cc b/tgt-blif/blif.cc
index 5b7016438..cdd9f7202 100644
--- a/tgt-blif/blif.cc
+++ b/tgt-blif/blif.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2013-2022 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2013-2023 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -35,7 +35,7 @@ using namespace std;
 
 static const char*version_string =
 "Icarus Verilog BLIF Code Generator " VERSION " (" VERSION_TAG ")\n\n"
-"Copyright (c) 2013-2020 Stephen Williams (steve@icarus.com)\n\n"
+"Copyright (c) 2013-2023 Stephen Williams (steve@icarus.com)\n\n"
 "  This program is free software; you can redistribute it and/or modify\n"
 "  it under the terms of the GNU General Public License as published by\n"
 "  the Free Software Foundation; either version 2 of the License, or\n"
diff --git a/tgt-null/null.c b/tgt-null/null.c
index 675c8c38a..fe7333aff 100644
--- a/tgt-null/null.c
+++ b/tgt-null/null.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2020 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2000-2023 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -30,7 +30,7 @@
 
 static const char*version_string =
 "Icarus Verilog NULL Code Generator " VERSION " (" VERSION_TAG ")\n\n"
-"Copyright (c) 2000-2020 Stephen Williams (steve@icarus.com)\n\n"
+"Copyright (c) 2000-2023 Stephen Williams (steve@icarus.com)\n\n"
 "  This program is free software; you can redistribute it and/or modify\n"
 "  it under the terms of the GNU General Public License as published by\n"
 "  the Free Software Foundation; either version 2 of the License, or\n"
diff --git a/tgt-pcb/pcb.cc b/tgt-pcb/pcb.cc
index aebc7c70c..95380b32f 100644
--- a/tgt-pcb/pcb.cc
+++ b/tgt-pcb/pcb.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2011-2020 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2011-2023 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -32,7 +32,7 @@
 
 static const char*version_string =
 "Icarus Verilog PCB Netlist Generator " VERSION " (" VERSION_TAG ")\n\n"
-"Copyright (c) 2011-2020 Stephen Williams (steve@icarus.com)\n\n"
+"Copyright (c) 2011-2023 Stephen Williams (steve@icarus.com)\n\n"
 "  This program is free software; you can redistribute it and/or modify\n"
 "  it under the terms of the GNU General Public License as published by\n"
 "  the Free Software Foundation; either version 2 of the License, or\n"
diff --git a/tgt-sizer/sizer.cc b/tgt-sizer/sizer.cc
index 6f2a4a426..d13d42130 100644
--- a/tgt-sizer/sizer.cc
+++ b/tgt-sizer/sizer.cc
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2014-2020 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2014-2023 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -34,7 +34,7 @@ using namespace std;
 
 static const char*version_string =
 "Icarus Verilog SIZER Statistics Generator " VERSION " (" VERSION_TAG ")\n\n"
-"Copyright (c) 2014-2020 Stephen Williams (steve@icarus.com)\n\n"
+"Copyright (c) 2014-2023 Stephen Williams (steve@icarus.com)\n\n"
 "  This program is free software; you can redistribute it and/or modify\n"
 "  it under the terms of the GNU General Public License as published by\n"
 "  the Free Software Foundation; either version 2 of the License, or\n"
diff --git a/tgt-stub/stub.c b/tgt-stub/stub.c
index 670962f7a..652ec0e57 100644
--- a/tgt-stub/stub.c
+++ b/tgt-stub/stub.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2021 Stephen Williams (steve@icarus.com)
+ * Copyright (c) 2000-2023 Stephen Williams (steve@icarus.com)
  *
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
@@ -36,7 +36,7 @@
 
 static const char*version_string =
 "Icarus Verilog STUB Code Generator " VERSION " (" VERSION_TAG ")\n\n"
-"Copyright (c) 2000-2020 Stephen Williams (steve@icarus.com)\n\n"
+"Copyright (c) 2000-2023 Stephen Williams (steve@icarus.com)\n\n"
 "  This program is free software; you can redistribute it and/or modify\n"
 "  it under the terms of the GNU General Public License as published by\n"
 "  the Free Software Foundation; either version 2 of the License, or\n"
diff --git a/tgt-vhdl/vhdl.cc b/tgt-vhdl/vhdl.cc
index afab4c9e0..ad7c16ff1 100644
--- a/tgt-vhdl/vhdl.cc
+++ b/tgt-vhdl/vhdl.cc
@@ -1,7 +1,7 @@
 /*
  *  VHDL code generator for Icarus Verilog.
  *
- *  Copyright (C) 2008-2021  Nick Gasson (nick@nickg.me.uk)
+ *  Copyright (C) 2008-2023  Nick Gasson (nick@nickg.me.uk)
  *
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
@@ -35,7 +35,7 @@ using namespace std;
 
 static const char*version_string =
 "Icarus Verilog VHDL Code Generator " VERSION " (" VERSION_TAG ")\n\n"
-"Copyright (C) 2008-2020  Nick Gasson (nick@nickg.me.uk)\n\n"
+"Copyright (C) 2008-2023  Nick Gasson (nick@nickg.me.uk)\n\n"
 "  This program is free software; you can redistribute it and/or modify\n"
 "  it under the terms of the GNU General Public License as published by\n"
 "  the Free Software Foundation; either version 2 of the License, or\n"
diff --git a/tgt-vlog95/vlog95.c b/tgt-vlog95/vlog95.c
index 208821b16..2555199be 100644
--- a/tgt-vlog95/vlog95.c
+++ b/tgt-vlog95/vlog95.c
@@ -1,5 +1,5 @@
 #define COPYRIGHT \
-  "Copyright (c) 2010-2021 Cary R. (cygcary@yahoo.com)"
+  "Copyright (c) 2010-2023 Cary R. (cygcary@yahoo.com)"
 /*
  *  This program is free software; you can redistribute it and/or modify
  *  it under the terms of the GNU General Public License as published by
diff --git a/tgt-vvp/vvp.c b/tgt-vvp/vvp.c
index 1856c9be3..68eaadb08 100644
--- a/tgt-vvp/vvp.c
+++ b/tgt-vvp/vvp.c
@@ -1,5 +1,5 @@
 #define COPYRIGHT \
-  "Copyright (c) 2001-2021 Stephen Williams (steve@icarus.com)"
+  "Copyright (c) 2001-2023 Stephen Williams (steve@icarus.com)"
 /*
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU
diff --git a/vvp/main.cc b/vvp/main.cc
index 83e0e8308..7253f0e47 100644
--- a/vvp/main.cc
+++ b/vvp/main.cc
@@ -1,5 +1,5 @@
 const char COPYRIGHT[] =
-  "Copyright (c) 2001-2021 Stephen Williams (steve@icarus.com)";
+  "Copyright (c) 2001-2023 Stephen Williams (steve@icarus.com)";
 /*
  *    This source code is free software; you can redistribute it
  *    and/or modify it in source code form under the terms of the GNU