diff --git a/src/arch/i386/core/gdbmach.c b/src/arch/i386/core/gdbmach.c
index 4d6897f7d..d92a4ac08 100644
--- a/src/arch/i386/core/gdbmach.c
+++ b/src/arch/i386/core/gdbmach.c
@@ -15,9 +15,13 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <stddef.h>
 #include <stdio.h>
diff --git a/src/arch/i386/drivers/net/undiload.c b/src/arch/i386/drivers/net/undiload.c
index 77134dcb8..7160ee384 100644
--- a/src/arch/i386/drivers/net/undiload.c
+++ b/src/arch/i386/drivers/net/undiload.c
@@ -15,9 +15,13 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <stdint.h>
 #include <stdlib.h>
diff --git a/src/arch/i386/prefix/kkpxeprefix.S b/src/arch/i386/prefix/kkpxeprefix.S
index d7dd31573..3c17dbdb1 100644
--- a/src/arch/i386/prefix/kkpxeprefix.S
+++ b/src/arch/i386/prefix/kkpxeprefix.S
@@ -3,7 +3,7 @@
  *****************************************************************************
  */
 
-FILE_LICENCE ( GPL2_OR_LATER )
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL )
 
 #define PXELOADER_KEEP_UNDI
 #define PXELOADER_KEEP_PXE
diff --git a/src/core/fnrec.c b/src/core/fnrec.c
index 3453c8b6a..0430817f8 100644
--- a/src/core/fnrec.c
+++ b/src/core/fnrec.c
@@ -15,9 +15,13 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <stdlib.h>
 #include <stdio.h>
diff --git a/src/core/gdbserial.c b/src/core/gdbserial.c
index 6f78c88bf..255acea71 100644
--- a/src/core/gdbserial.c
+++ b/src/core/gdbserial.c
@@ -15,9 +15,13 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <assert.h>
 #include <ipxe/serial.h>
diff --git a/src/core/gdbstub.c b/src/core/gdbstub.c
index af06118b2..6ad52d1a6 100644
--- a/src/core/gdbstub.c
+++ b/src/core/gdbstub.c
@@ -15,9 +15,13 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 /**
  * @file
diff --git a/src/core/gdbudp.c b/src/core/gdbudp.c
index 5977547c8..e4613d137 100644
--- a/src/core/gdbudp.c
+++ b/src/core/gdbudp.c
@@ -15,9 +15,13 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <stdio.h>
 #include <string.h>
diff --git a/src/drivers/net/virtio-net.c b/src/drivers/net/virtio-net.c
index d5fd81979..8b67d9dd9 100644
--- a/src/drivers/net/virtio-net.c
+++ b/src/drivers/net/virtio-net.c
@@ -20,7 +20,7 @@
  * See the COPYING file in the top-level directory.
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <errno.h>
 #include <stdlib.h>
diff --git a/src/drivers/net/vxge/vxge.c b/src/drivers/net/vxge/vxge.c
index 9c587722b..d50ac05b5 100644
--- a/src/drivers/net/vxge/vxge.c
+++ b/src/drivers/net/vxge/vxge.c
@@ -5,7 +5,7 @@
  * as "vxge" even though the code is in vxge_* named files.
  */
 
-FILE_LICENCE(GPL2_OR_LATER);
+FILE_LICENCE(GPL2_OR_LATER_OR_UBDL);
 
 #include <ipxe/pci.h>
 
diff --git a/src/hci/commands/gdbstub_cmd.c b/src/hci/commands/gdbstub_cmd.c
index 33890aebc..c4a831e7a 100644
--- a/src/hci/commands/gdbstub_cmd.c
+++ b/src/hci/commands/gdbstub_cmd.c
@@ -15,9 +15,13 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <stdio.h>
 #include <errno.h>
diff --git a/src/include/ipxe/gdbserial.h b/src/include/ipxe/gdbserial.h
index a3b56173c..d02fb8d1b 100644
--- a/src/include/ipxe/gdbserial.h
+++ b/src/include/ipxe/gdbserial.h
@@ -7,7 +7,7 @@
  *
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 struct gdb_transport;
 
diff --git a/src/include/ipxe/gdbstub.h b/src/include/ipxe/gdbstub.h
index 319606747..13ca33ddb 100644
--- a/src/include/ipxe/gdbstub.h
+++ b/src/include/ipxe/gdbstub.h
@@ -7,7 +7,7 @@
  *
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <stdint.h>
 #include <ipxe/tables.h>
diff --git a/src/include/ipxe/gdbudp.h b/src/include/ipxe/gdbudp.h
index db7a451c9..a1c091522 100644
--- a/src/include/ipxe/gdbudp.h
+++ b/src/include/ipxe/gdbudp.h
@@ -7,7 +7,7 @@
  *
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 struct sockaddr_in;
 struct gdb_transport;
diff --git a/src/include/ipxe/serial.h b/src/include/ipxe/serial.h
index b47b1d125..86d05370d 100644
--- a/src/include/ipxe/serial.h
+++ b/src/include/ipxe/serial.h
@@ -7,7 +7,7 @@
  *
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 extern void serial_putc ( int ch );
 extern int serial_getc ( void );
diff --git a/src/net/vlan.c b/src/net/vlan.c
index b4ddde42d..49e3257a0 100644
--- a/src/net/vlan.c
+++ b/src/net/vlan.c
@@ -15,9 +15,13 @@
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
  */
 
-FILE_LICENCE ( GPL2_OR_LATER );
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
 
 #include <stdint.h>
 #include <string.h>