diff --git a/src/mame/drivers/chaknpop.c b/src/mame/drivers/chaknpop.c
index acdb500010a..742b1df5516 100644
--- a/src/mame/drivers/chaknpop.c
+++ b/src/mame/drivers/chaknpop.c
@@ -1,4 +1,4 @@
-// license:???
+// license:BSD-3-Clause
 // copyright-holders:BUT
 /*
 
diff --git a/src/mame/drivers/tceptor.c b/src/mame/drivers/tceptor.c
index 5d34f719898..ed0a1d79207 100644
--- a/src/mame/drivers/tceptor.c
+++ b/src/mame/drivers/tceptor.c
@@ -1,4 +1,4 @@
-// license:???
+// license:BSD-3-Clause
 // copyright-holders:BUT
 /*
  *  Thunder Ceptor board
diff --git a/src/mame/includes/chaknpop.h b/src/mame/includes/chaknpop.h
index aeace190c69..4806d02e7ce 100644
--- a/src/mame/includes/chaknpop.h
+++ b/src/mame/includes/chaknpop.h
@@ -1,4 +1,4 @@
-// license:???
+// license:BSD-3-Clause
 // copyright-holders:BUT
 
 
diff --git a/src/mame/includes/tceptor.h b/src/mame/includes/tceptor.h
index c22c72491f9..b7dcb5ae142 100644
--- a/src/mame/includes/tceptor.h
+++ b/src/mame/includes/tceptor.h
@@ -1,4 +1,4 @@
-// license:???
+// license:BSD-3-Clause
 // copyright-holders:BUT
 #include "sound/dac.h"
 #include "sound/namco.h"
diff --git a/src/mame/machine/chaknpop.c b/src/mame/machine/chaknpop.c
index c718487801b..c6f31df3312 100644
--- a/src/mame/machine/chaknpop.c
+++ b/src/mame/machine/chaknpop.c
@@ -1,4 +1,4 @@
-// license:???
+// license:BSD-3-Clause
 // copyright-holders:BUT
 /*
  *  Chack'n Pop (C) 1983 TAITO Corp.
diff --git a/src/mame/video/chaknpop.c b/src/mame/video/chaknpop.c
index 9e75e1014da..f6d3c83ce5b 100644
--- a/src/mame/video/chaknpop.c
+++ b/src/mame/video/chaknpop.c
@@ -1,4 +1,4 @@
-// license:???
+// license:BSD-3-Clause
 // copyright-holders:BUT
 /*
  *  Chack'n Pop (C) 1983 TAITO Corp.
diff --git a/src/mame/video/tceptor.c b/src/mame/video/tceptor.c
index 117fd909331..e419140eda6 100644
--- a/src/mame/video/tceptor.c
+++ b/src/mame/video/tceptor.c
@@ -1,4 +1,4 @@
-// license:???
+// license:BSD-3-Clause
 // copyright-holders:BUT
 /*
  *  Thunder Ceptor board