diff --git a/README.md b/README.md
index 2ce63237b..2d0db60aa 100755
--- a/README.md
+++ b/README.md
@@ -2021,7 +2021,7 @@ Winlin
 [more0]: http://winlinvip.github.io/srs.release/releases/
 [more1]: http://ossrs.net/srs.release/releases/
 
-[LICENSE]: https://github.com/ossrs/srs/blob/4.0release/LICENSE
+[LICENSE]: https://github.com/ossrs/srs/blob/develop/LICENSE
 [LicenseMixing]: https://github.com/ossrs/srs/wiki/LicenseMixing
 
 [srs_CN]: https://github.com/ossrs/srs/wiki/v4_CN_Home
diff --git a/trunk/src/core/srs_core_version5.cpp b/trunk/src/core/srs_core_version5.cpp
index e5071d6ef..f9f3e85da 100644
--- a/trunk/src/core/srs_core_version5.cpp
+++ b/trunk/src/core/srs_core_version5.cpp
@@ -1,24 +1,7 @@
-/**
- * The MIT License (MIT)
- *
- * Copyright (c) 2013-2020 Winlin
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy of
- * this software and associated documentation files (the "Software"), to deal in
- * the Software without restriction, including without limitation the rights to
- * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
- * the Software, and to permit persons to whom the Software is furnished to do so,
- * subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
- * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
- * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
- * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- */
+//
+// Copyright (c) 2013-2021 Winlin
+//
+// SPDX-License-Identifier: MIT
+//
 
 #include <srs_core_version4.hpp>
diff --git a/trunk/src/core/srs_core_version5.hpp b/trunk/src/core/srs_core_version5.hpp
index be5ddc9e6..a31d97a55 100644
--- a/trunk/src/core/srs_core_version5.hpp
+++ b/trunk/src/core/srs_core_version5.hpp
@@ -1,25 +1,8 @@
-/**
- * The MIT License (MIT)
- *
- * Copyright (c) 2013-2020 Winlin
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy of
- * this software and associated documentation files (the "Software"), to deal in
- * the Software without restriction, including without limitation the rights to
- * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
- * the Software, and to permit persons to whom the Software is furnished to do so,
- * subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in all
- * copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
- * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
- * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
- * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- */
+//
+// Copyright (c) 2013-2021 Winlin
+//
+// SPDX-License-Identifier: MIT
+//
 
 #ifndef SRS_CORE_VERSION5_HPP
 #define SRS_CORE_VERSION5_HPP