diff --git a/src/chat/client/main.c b/src/chat/client/main.c
index 96f027b..8b8d3f5 100644
--- a/src/chat/client/main.c
+++ b/src/chat/client/main.c
@@ -1,3 +1,21 @@
+/*
+This is part of WHY2
+Copyright (C) 2022 Václav Šmejkal
+
+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 3 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 <https://www.gnu.org/licenses/>.
+*/
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/socket.h>
diff --git a/src/chat/server/main.c b/src/chat/server/main.c
index a554935..19b0d7a 100644
--- a/src/chat/server/main.c
+++ b/src/chat/server/main.c
@@ -1,3 +1,21 @@
+/*
+This is part of WHY2
+Copyright (C) 2022 Václav Šmejkal
+
+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 3 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 <https://www.gnu.org/licenses/>.
+*/
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/socket.h>