diff --git a/agent/sim/core.cc b/agent/sim/core.cc
index 791caae..8537eeb 100644
--- a/agent/sim/core.cc
+++ b/agent/sim/core.cc
@@ -1,19 +1,18 @@
 /*
-    Copyright (C) 2018 Open Networking Foundation
+ * Copyright 2018-present Open Networking Foundation
 
-    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.
+ * 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
 
-    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.
+ * http://www.apache.org/licenses/LICENSE-2.0
 
-    You should have received a copy of the GNU General Public License
-    along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
+ * 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.
+ */
 
 #include <iostream>
 #include <memory>
diff --git a/agent/sim/core.h b/agent/sim/core.h
index f656b1f..ed0fb4d 100644
--- a/agent/sim/core.h
+++ b/agent/sim/core.h
@@ -1,19 +1,18 @@
 /*
-    Copyright (C) 2018 Open Networking Foundation
+ * Copyright 2018-present Open Networking Foundation
 
-    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.
+ * 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
 
-    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.
+ * http://www.apache.org/licenses/LICENSE-2.0
 
-    You should have received a copy of the GNU General Public License
-    along with this program.  If not, see <http://www.gnu.org/licenses/>.
-*/
+ * 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.
+ */
 
 #ifndef OPENOLT_CORE_H_
 #define OPENOLT_CORE_H_