diff --git a/src/gb/common_vty.c b/src/gb/common_vty.c
index 16f3bbd..a47294b 100644
--- a/src/gb/common_vty.c
+++ b/src/gb/common_vty.c
@@ -5,6 +5,8 @@
  * (C) 2009-2010 by Holger Hans Peter Freyther
  * All Rights Reserved
  *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
  * 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
  * the Free Software Foundation; either version 2 of the License, or
diff --git a/src/gb/gprs_bssgp.c b/src/gb/gprs_bssgp.c
index b906643..520868e 100644
--- a/src/gb/gprs_bssgp.c
+++ b/src/gb/gprs_bssgp.c
@@ -5,6 +5,8 @@
  *
  * All Rights Reserved
  *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
  * 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
  * the Free Software Foundation; either version 2 of the License, or
diff --git a/src/gb/gprs_bssgp_bss.c b/src/gb/gprs_bssgp_bss.c
index d9f04c5..3939e25 100644
--- a/src/gb/gprs_bssgp_bss.c
+++ b/src/gb/gprs_bssgp_bss.c
@@ -5,6 +5,8 @@
  *
  * All Rights Reserved
  *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
  * 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
  * the Free Software Foundation; either version 2 of the License, or
diff --git a/src/gb/gprs_bssgp_util.c b/src/gb/gprs_bssgp_util.c
index 4553da8..669dfb8 100644
--- a/src/gb/gprs_bssgp_util.c
+++ b/src/gb/gprs_bssgp_util.c
@@ -5,6 +5,8 @@
  *
  * All Rights Reserved
  *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
  * 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
  * the Free Software Foundation; either version 2 of the License, or
diff --git a/src/gb/gprs_bssgp_vty.c b/src/gb/gprs_bssgp_vty.c
index f787846..6131e6b 100644
--- a/src/gb/gprs_bssgp_vty.c
+++ b/src/gb/gprs_bssgp_vty.c
@@ -5,6 +5,8 @@
  *
  * All Rights Reserved
  *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
  * 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
  * the Free Software Foundation; either version 2 of the License, or
diff --git a/src/gb/gprs_ns.c b/src/gb/gprs_ns.c
index a00c8e5..47d170d 100644
--- a/src/gb/gprs_ns.c
+++ b/src/gb/gprs_ns.c
@@ -2,10 +2,13 @@
  * GPRS Networks Service (NS) messages on the Gb interface.
  * 3GPP TS 08.16 version 8.0.1 Release 1999 / ETSI TS 101 299 V8.0.1 (2002-05). */
 /*
- * (C) 2009-2012 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2009-2017 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2016-2017 sysmocom - s.f.m.c. GmbH
  *
  * All Rights Reserved
  *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
  * 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
  * the Free Software Foundation; either version 2 of the License, or
diff --git a/src/gb/gprs_ns_frgre.c b/src/gb/gprs_ns_frgre.c
index 52145ff..483fdb6 100644
--- a/src/gb/gprs_ns_frgre.c
+++ b/src/gb/gprs_ns_frgre.c
@@ -3,10 +3,12 @@
  * GPRS Networks Service (NS) messages on the Gb interface,
  * 3GPP TS 08.16 version 8.0.1 Release 1999 / ETSI TS 101 299 V8.0.1 (2002-05). */
 /*
- * (C) 2009-2010 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2009-2010,2014,2017 by Harald Welte <laforge@gnumonks.org>
  *
  * All Rights Reserved
  *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
  * 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
  * the Free Software Foundation; either version 2 of the License, or
diff --git a/src/gb/gprs_ns_vty.c b/src/gb/gprs_ns_vty.c
index e8ef2a2..667db7d 100644
--- a/src/gb/gprs_ns_vty.c
+++ b/src/gb/gprs_ns_vty.c
@@ -1,10 +1,13 @@
 /*! \file gprs_ns_vty.c
  * VTY interface for our GPRS Networks Service (NS) implementation. */
 /*
- * (C) 2009-2010 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2009-2014 by Harald Welte <laforge@gnumonks.org>
+ * (C) 2016-2017 by sysmocom - s.f.m.c. GmbH
  *
  * All Rights Reserved
  *
+ * SPDX-License-Identifier: GPL-2.0+
+ *
  * 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
  * the Free Software Foundation; either version 2 of the License, or