diff --git a/lib/dnssd.h b/lib/dnssd.h
index 9a82ee4..17cb5d7 100644
--- a/lib/dnssd.h
+++ b/lib/dnssd.h
@@ -1,3 +1,17 @@
+/**
+ *  Copyright (C) 2012  Juho Vähä-Herttua
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library 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
+ *  Lesser General Public License for more details.
+ */
+
 #ifndef DNSSD_H
 #define DNSSD_H
 
@@ -36,4 +50,4 @@ DNSSD_API void dnssd_destroy(dnssd_t *dnssd);
 #ifdef __cplusplus
 }
 #endif
-#endif
\ No newline at end of file
+#endif
diff --git a/lib/dnssdint.h b/lib/dnssdint.h
index 862316b..0879b0b 100644
--- a/lib/dnssdint.h
+++ b/lib/dnssdint.h
@@ -1,3 +1,17 @@
+/**
+ *  Copyright (C) 2012  Juho Vähä-Herttua
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library 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
+ *  Lesser General Public License for more details.
+ */
+
 #ifndef DNSSDINT_H
 #define DNSSDINT_H
 
diff --git a/lib/fairplay.h b/lib/fairplay.h
index d520817..2b7c30f 100644
--- a/lib/fairplay.h
+++ b/lib/fairplay.h
@@ -1,3 +1,17 @@
+/**
+ *  Copyright (C) 2018  Juho Vähä-Herttua
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library 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
+ *  Lesser General Public License for more details.
+ */
+
 #ifndef FAIRPLAY_H
 #define FAIRPLAY_H
 
diff --git a/lib/fairplay_playfair.c b/lib/fairplay_playfair.c
index ade48d9..8308c77 100644
--- a/lib/fairplay_playfair.c
+++ b/lib/fairplay_playfair.c
@@ -1,3 +1,17 @@
+/**
+ *  Copyright (C) 2018  Juho Vähä-Herttua
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library 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
+ *  Lesser General Public License for more details.
+ */
+
 #include <stdlib.h>
 #include <string.h>
 #include <assert.h>
diff --git a/lib/global.h b/lib/global.h
index d3242ba..62be812 100644
--- a/lib/global.h
+++ b/lib/global.h
@@ -1,3 +1,17 @@
+/**
+ *  Copyright (C) 2012  Juho Vähä-Herttua
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library 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
+ *  Lesser General Public License for more details.
+ */
+
 #ifndef GLOBAL_H
 #define GLOBAL_H
 
diff --git a/lib/raop.h b/lib/raop.h
index deefaf2..85f30e2 100644
--- a/lib/raop.h
+++ b/lib/raop.h
@@ -1,3 +1,17 @@
+/**
+ *  Copyright (C) 2012-2015  Juho Vähä-Herttua
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Lesser General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2.1 of the License, or (at your option) any later version.
+ *
+ *  This library 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
+ *  Lesser General Public License for more details.
+ */
+
 #ifndef RAOP_H
 #define RAOP_H