diff --git a/src/mibew/styles/default/chat.css b/src/mibew/styles/default/chat.css
index c2ff8ba4..c96d8cbb 100644
--- a/src/mibew/styles/default/chat.css
+++ b/src/mibew/styles/default/chat.css
@@ -1,3 +1,21 @@
+/*
+ * This file is a part of Mibew Messenger.
+ *
+ * Copyright 2005-2014 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 a {
 	text-decoration: underline;
 }
diff --git a/src/mibew/styles/original/chat.css b/src/mibew/styles/original/chat.css
index c934e164..d906c206 100644
--- a/src/mibew/styles/original/chat.css
+++ b/src/mibew/styles/original/chat.css
@@ -1,3 +1,21 @@
+/*
+ * This file is a part of Mibew Messenger.
+ *
+ * Copyright 2005-2014 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 a {
 	text-decoration: underline;
 }
diff --git a/src/mibew/styles/silver/chat.css b/src/mibew/styles/silver/chat.css
index c00fe5b5..0cd97365 100644
--- a/src/mibew/styles/silver/chat.css
+++ b/src/mibew/styles/silver/chat.css
@@ -1,3 +1,21 @@
+/*
+ * This file is a part of Mibew Messenger.
+ *
+ * Copyright 2005-2014 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 html, body {
 	height: 100%;
 }
diff --git a/src/mibew/styles/simplicity/chat.css b/src/mibew/styles/simplicity/chat.css
index b90caee5..efa2dafc 100644
--- a/src/mibew/styles/simplicity/chat.css
+++ b/src/mibew/styles/simplicity/chat.css
@@ -1,3 +1,21 @@
+/*
+ * This file is a part of Mibew Messenger.
+ *
+ * Copyright 2005-2014 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 BODY {
 	margin: 0px;
 	font-family: Verdana, Arial, Helvetica, sans-serif;