diff --git a/sbin/ipfw/altq.c b/sbin/ipfw/altq.c
index 8398ab611f2..a78852cfd63 100644
--- a/sbin/ipfw/altq.c
+++ b/sbin/ipfw/altq.c
@@ -1,4 +1,6 @@
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ * 
  * Copyright (c) 2002-2003 Luigi Rizzo
  * Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp
  * Copyright (c) 1994 Ugen J.S.Antsilevich
diff --git a/sbin/ipfw/dummynet.c b/sbin/ipfw/dummynet.c
index 0aa3bb5c1e3..e3a04b389eb 100644
--- a/sbin/ipfw/dummynet.c
+++ b/sbin/ipfw/dummynet.c
@@ -1,4 +1,6 @@
-/*
+/*.
+ * SPDX-License-Identifier: BSD-2-Clause
+ * 
  * Codel/FQ_Codel and PIE/FQ_PIE Code:
  * Copyright (C) 2016 Centre for Advanced Internet Architectures,
  *  Swinburne University of Technology, Melbourne, Australia.
diff --git a/sbin/ipfw/ipfw2.c b/sbin/ipfw/ipfw2.c
index 7c491466cbb..455669763bf 100644
--- a/sbin/ipfw/ipfw2.c
+++ b/sbin/ipfw/ipfw2.c
@@ -1,4 +1,6 @@
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ * 
  * Copyright (c) 2002-2003 Luigi Rizzo
  * Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp
  * Copyright (c) 1994 Ugen J.S.Antsilevich
diff --git a/sbin/ipfw/ipfw2.h b/sbin/ipfw/ipfw2.h
index 8befdc91cc9..274c0008a95 100644
--- a/sbin/ipfw/ipfw2.h
+++ b/sbin/ipfw/ipfw2.h
@@ -1,4 +1,6 @@
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ * 
  * Copyright (c) 2002-2003 Luigi Rizzo
  * Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp
  * Copyright (c) 1994 Ugen J.S.Antsilevich
diff --git a/sbin/ipfw/ipv6.c b/sbin/ipfw/ipv6.c
index 4fce1d2a288..5c643ca911e 100644
--- a/sbin/ipfw/ipv6.c
+++ b/sbin/ipfw/ipv6.c
@@ -1,4 +1,6 @@
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ * 
  * Copyright (c) 2002-2003 Luigi Rizzo
  * Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp
  * Copyright (c) 1994 Ugen J.S.Antsilevich
diff --git a/sbin/ipfw/main.c b/sbin/ipfw/main.c
index b7ff07a6094..0ea0bb7cb63 100644
--- a/sbin/ipfw/main.c
+++ b/sbin/ipfw/main.c
@@ -1,4 +1,6 @@
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ * 
  * Copyright (c) 2002-2003,2010 Luigi Rizzo
  * Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp
  * Copyright (c) 1994 Ugen J.S.Antsilevich
diff --git a/sbin/ipfw/nat.c b/sbin/ipfw/nat.c
index 28dac8645bf..70a50de947c 100644
--- a/sbin/ipfw/nat.c
+++ b/sbin/ipfw/nat.c
@@ -1,4 +1,6 @@
-/*
+/*-
+ * SPDX-License-Identifier: BSD-2-Clause
+ * 
  * Copyright (c) 2002-2003 Luigi Rizzo
  * Copyright (c) 1996 Alex Nash, Paul Traina, Poul-Henning Kamp
  * Copyright (c) 1994 Ugen J.S.Antsilevich
diff --git a/sys/sys/msg.h b/sys/sys/msg.h
index a0a963d551d..d2e9f756d5d 100644
--- a/sys/sys/msg.h
+++ b/sys/sys/msg.h
@@ -6,7 +6,7 @@
  *
  * Author:  Daniel Boulet
  *
- * SPDX-License-Identifier: BSD-1-Clause
+ * SPDX-License-Identifier: BSD-2-Clause
  *
  * Copyright 1993 Daniel Boulet and RTMX Inc.
  *
diff --git a/sys/sys/snoop.h b/sys/sys/snoop.h
index f2d6b31a903..1a5e117976f 100644
--- a/sys/sys/snoop.h
+++ b/sys/sys/snoop.h
@@ -1,5 +1,5 @@
 /*-
- * SPDX-License-Identifier: BSD-1-Clause
+ * SPDX-License-Identifier: BSD-2-Clause
  *
  * Copyright (c) 1995 Ugen J.S.Antsilevich
  *
diff --git a/usr.sbin/watch/watch.c b/usr.sbin/watch/watch.c
index e0999757ab6..3585d4555b1 100644
--- a/usr.sbin/watch/watch.c
+++ b/usr.sbin/watch/watch.c
@@ -1,5 +1,5 @@
 /*-
- * SPDX-License-Identifier: BSD-1-Clause
+ * SPDX-License-Identifier: BSD-2-Clause
  *
  * Copyright (c) 1995 Ugen J.S.Antsilevich
  *