diff --git a/keyboards/ciaanh/kanagawa/ansi/ansi.c b/keyboards/ciaanh/kanagawa/ansi/ansi.c
index 879f68dc186..faac5f0f995 100644
--- a/keyboards/ciaanh/kanagawa/ansi/ansi.c
+++ b/keyboards/ciaanh/kanagawa/ansi/ansi.c
@@ -1,4 +1,20 @@
-#include "kanagawa.h"
+/* Copyright 2023 Ciaanh (@ciaanh)
+ *
+ * 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
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+ #include "kanagawa.h"
 
 #ifdef RGB_MATRIX_ENABLE
 #   define RGB_MATRIX_LED_COUNT 82
diff --git a/keyboards/ciaanh/kanagawa/ansi/ansi.h b/keyboards/ciaanh/kanagawa/ansi/ansi.h
index 6f70f09beec..1de201d1c0a 100644
--- a/keyboards/ciaanh/kanagawa/ansi/ansi.h
+++ b/keyboards/ciaanh/kanagawa/ansi/ansi.h
@@ -1 +1,17 @@
-#pragma once
+/* Copyright 2023 Ciaanh (@ciaanh)
+ *
+ * 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
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+ #pragma once
diff --git a/keyboards/ciaanh/kanagawa/ansi/keymaps/default/keymap.c b/keyboards/ciaanh/kanagawa/ansi/keymaps/default/keymap.c
index 7ac53f1a65a..371f09cd19e 100644
--- a/keyboards/ciaanh/kanagawa/ansi/keymaps/default/keymap.c
+++ b/keyboards/ciaanh/kanagawa/ansi/keymaps/default/keymap.c
@@ -1,4 +1,20 @@
-#include QMK_KEYBOARD_H
+/* Copyright 2023 Ciaanh (@ciaanh)
+ *
+ * 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
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+ #include QMK_KEYBOARD_H
 
 /* Keyboard layout
 *   ,---------.   ,---------------------------------------.  ,---------------------------------------.  ,---------------------------------------.    ,---------.
diff --git a/keyboards/ciaanh/kanagawa/ansi/keymaps/default/rgb_matrix_user.inc b/keyboards/ciaanh/kanagawa/ansi/keymaps/default/rgb_matrix_user.inc
deleted file mode 100644
index ed2ed30106f..00000000000
--- a/keyboards/ciaanh/kanagawa/ansi/keymaps/default/rgb_matrix_user.inc
+++ /dev/null
@@ -1,40 +0,0 @@
-// !!! DO NOT ADD #pragma once !!! //
-
-// Step 1.
-// Declare custom effects using the RGB_MATRIX_EFFECT macro
-// (note the lack of semicolon after the macro!)
-RGB_MATRIX_EFFECT(my_cool_effect)
-RGB_MATRIX_EFFECT(my_cool_effect2)
-
-// Step 2.
-// Define effects inside the `RGB_MATRIX_CUSTOM_EFFECT_IMPLS` ifdef block
-#ifdef RGB_MATRIX_CUSTOM_EFFECT_IMPLS
-
-// e.g: A simple effect, self-contained within a single method
-static bool my_cool_effect(effect_params_t* params) {
-  RGB_MATRIX_USE_LIMITS(led_min, led_max);
-  for (uint8_t i = led_min; i < led_max; i++) {
-    rgb_matrix_set_color(i, 0xff, 0xff, 0x00);
-  }
-  return rgb_matrix_check_finished_leds(led_max);
-}
-
-// e.g: A more complex effect, relying on external methods and state, with
-// dedicated init and run methods
-static uint8_t some_global_state;
-static void my_cool_effect2_complex_init(effect_params_t* params) {
-  some_global_state = 1;
-}
-static bool my_cool_effect2_complex_run(effect_params_t* params) {
-  RGB_MATRIX_USE_LIMITS(led_min, led_max);
-  for (uint8_t i = led_min; i < led_max; i++) {
-    rgb_matrix_set_color(i, 0xff, some_global_state++, 0xff);
-  }
-  return rgb_matrix_check_finished_leds(led_max);
-}
-static bool my_cool_effect2(effect_params_t* params) {
-  if (params->init) my_cool_effect2_complex_init(params);
-  return my_cool_effect2_complex_run(params);
-}
-
-#endif // RGB_MATRIX_CUSTOM_EFFECT_IMPLS
\ No newline at end of file
diff --git a/keyboards/ciaanh/kanagawa/ansi/keymaps/via/keymap.c b/keyboards/ciaanh/kanagawa/ansi/keymaps/via/keymap.c
index 7ac53f1a65a..371f09cd19e 100644
--- a/keyboards/ciaanh/kanagawa/ansi/keymaps/via/keymap.c
+++ b/keyboards/ciaanh/kanagawa/ansi/keymaps/via/keymap.c
@@ -1,4 +1,20 @@
-#include QMK_KEYBOARD_H
+/* Copyright 2023 Ciaanh (@ciaanh)
+ *
+ * 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
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+ #include QMK_KEYBOARD_H
 
 /* Keyboard layout
 *   ,---------.   ,---------------------------------------.  ,---------------------------------------.  ,---------------------------------------.    ,---------.
diff --git a/keyboards/ciaanh/kanagawa/config.h b/keyboards/ciaanh/kanagawa/config.h
index c85bd4c2bc6..60b87421133 100644
--- a/keyboards/ciaanh/kanagawa/config.h
+++ b/keyboards/ciaanh/kanagawa/config.h
@@ -1,4 +1,20 @@
-#pragma once
+/* Copyright 2023 Ciaanh (@ciaanh)
+ *
+ * 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
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+ #pragma once
 
 /* OLED SPI Defines */
 #ifdef OLED_ENABLE
diff --git a/keyboards/ciaanh/kanagawa/iso/iso.c b/keyboards/ciaanh/kanagawa/iso/iso.c
index 43fd253b96b..712029d8846 100644
--- a/keyboards/ciaanh/kanagawa/iso/iso.c
+++ b/keyboards/ciaanh/kanagawa/iso/iso.c
@@ -1,4 +1,20 @@
-#include "kanagawa.h"
+/* Copyright 2023 Ciaanh (@ciaanh)
+ *
+ * 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
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+ #include "kanagawa.h"
 
 #ifdef RGB_MATRIX_ENABLE
 
diff --git a/keyboards/ciaanh/kanagawa/iso/iso.h b/keyboards/ciaanh/kanagawa/iso/iso.h
index 7b9637ef9c2..69cbd9c747c 100644
--- a/keyboards/ciaanh/kanagawa/iso/iso.h
+++ b/keyboards/ciaanh/kanagawa/iso/iso.h
@@ -1 +1,17 @@
-#pragma once
\ No newline at end of file
+/* Copyright 2023 Ciaanh (@ciaanh)
+ *
+ * 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
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+ #pragma once
\ No newline at end of file
diff --git a/keyboards/ciaanh/kanagawa/kanagawa.c b/keyboards/ciaanh/kanagawa/kanagawa.c
index 2b7f0847711..d5fa70946ba 100644
--- a/keyboards/ciaanh/kanagawa/kanagawa.c
+++ b/keyboards/ciaanh/kanagawa/kanagawa.c
@@ -1 +1,17 @@
-#include "kanagawa.h"
+/* Copyright 2023 Ciaanh (@ciaanh)
+ *
+ * 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
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+ #include "kanagawa.h"
diff --git a/keyboards/ciaanh/kanagawa/kanagawa.h b/keyboards/ciaanh/kanagawa/kanagawa.h
index 52b8acc89bc..cc3fa9ffc0b 100644
--- a/keyboards/ciaanh/kanagawa/kanagawa.h
+++ b/keyboards/ciaanh/kanagawa/kanagawa.h
@@ -1,4 +1,20 @@
-#pragma once
+/* Copyright 2023 Ciaanh (@ciaanh)
+ *
+ * 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
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+ #pragma once
 
 #include "quantum.h"
 
diff --git a/keyboards/ciaanh/kanagawa/lib/oledfont.c b/keyboards/ciaanh/kanagawa/lib/oledfont.c
index 153007ef1a3..6860b746853 100644
--- a/keyboards/ciaanh/kanagawa/lib/oledfont.c
+++ b/keyboards/ciaanh/kanagawa/lib/oledfont.c
@@ -1,6 +1,20 @@
-#include "progmem.h"
-
-
+/* Copyright 2023 Ciaanh (@ciaanh)
+ *
+ * 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
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+ #include "progmem.h"
 
 const unsigned char font[] PROGMEM = {
     0x00, 0x00, 0x00, 0x00, 0x00, 0x00,              // 0x00 000 =>
diff --git a/keyboards/ciaanh/kanagawa/mcuconf.h b/keyboards/ciaanh/kanagawa/mcuconf.h
index f6378664da8..fd272f8b1c5 100644
--- a/keyboards/ciaanh/kanagawa/mcuconf.h
+++ b/keyboards/ciaanh/kanagawa/mcuconf.h
@@ -1,4 +1,20 @@
-#pragma once
+/* Copyright 2023 Ciaanh (@ciaanh)
+ *
+ * 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
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+ 
+ #pragma once
 
 #include_next <mcuconf.h>