diff --git a/beeref/__main__.py b/beeref/__main__.py
index 4623ef3..6e05f43 100755
--- a/beeref/__main__.py
+++ b/beeref/__main__.py
@@ -1,5 +1,20 @@
 #!/usr/bin/env python3
 
+# This file is part of BeeRef.
+#
+# BeeRef 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 3 of the License, or
+# (at your option) any later version.
+#
+# BeeRef 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 BeeRef.  If not, see <https://www.gnu.org/licenses/>.
+
 import logging
 import os.path
 import signal
diff --git a/beeref/bee_json.py b/beeref/bee_json.py
index 330b389..54c7229 100644
--- a/beeref/bee_json.py
+++ b/beeref/bee_json.py
@@ -1,3 +1,18 @@
+# This file is part of BeeRef.
+#
+# BeeRef 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 3 of the License, or
+# (at your option) any later version.
+#
+# BeeRef 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 BeeRef.  If not, see <https://www.gnu.org/licenses/>.
+
 import json
 
 from beeref.items import BeePixmapItem
diff --git a/beeref/gui.py b/beeref/gui.py
index fbaf4f9..3c0ee1b 100644
--- a/beeref/gui.py
+++ b/beeref/gui.py
@@ -1,3 +1,18 @@
+# This file is part of BeeRef.
+#
+# BeeRef 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 3 of the License, or
+# (at your option) any later version.
+#
+# BeeRef 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 BeeRef.  If not, see <https://www.gnu.org/licenses/>.
+
 import logging
 
 from PyQt6 import QtCore, QtGui, QtWidgets
diff --git a/beeref/items.py b/beeref/items.py
index a5b923c..d81d6c0 100644
--- a/beeref/items.py
+++ b/beeref/items.py
@@ -1,3 +1,18 @@
+# This file is part of BeeRef.
+#
+# BeeRef 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 3 of the License, or
+# (at your option) any later version.
+#
+# BeeRef 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 BeeRef.  If not, see <https://www.gnu.org/licenses/>.
+
 import base64
 import logging
 
diff --git a/beeref/scene.py b/beeref/scene.py
index 1697fa0..7489d16 100644
--- a/beeref/scene.py
+++ b/beeref/scene.py
@@ -1,3 +1,18 @@
+# This file is part of BeeRef.
+#
+# BeeRef 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 3 of the License, or
+# (at your option) any later version.
+#
+# BeeRef 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 BeeRef.  If not, see <https://www.gnu.org/licenses/>.
+
 import logging
 import math
 
diff --git a/beeref/selection.py b/beeref/selection.py
index fafc534..32cd50a 100644
--- a/beeref/selection.py
+++ b/beeref/selection.py
@@ -1,3 +1,18 @@
+# This file is part of BeeRef.
+#
+# BeeRef 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 3 of the License, or
+# (at your option) any later version.
+#
+# BeeRef 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 BeeRef.  If not, see <https://www.gnu.org/licenses/>.
+
 import logging
 
 from PyQt6 import QtCore, QtGui, QtWidgets
diff --git a/beeref/view.py b/beeref/view.py
index f562235..46e852e 100644
--- a/beeref/view.py
+++ b/beeref/view.py
@@ -1,3 +1,18 @@
+# This file is part of BeeRef.
+#
+# BeeRef 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 3 of the License, or
+# (at your option) any later version.
+#
+# BeeRef 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 BeeRef.  If not, see <https://www.gnu.org/licenses/>.
+
 import logging
 
 from PyQt6 import QtCore, QtGui, QtWidgets