diff --git a/test/Channel.t.sol b/test/Channel.t.sol
index 0006def..104c9e1 100644
--- a/test/Channel.t.sol
+++ b/test/Channel.t.sol
@@ -1,20 +1,4 @@
-// This file is part of Darwinia.
-// Copyright (C) 2018-2023 Darwinia Network
-// SPDX-License-Identifier: GPL-3.0
-//
-// Darwinia 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.
-//
-// Darwinia 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 Darwinia. If not, see <https://www.gnu.org/licenses/>.
-
+// SPDX-License-Identifier: MIT
 pragma solidity 0.8.17;
 
 import "forge-std/Test.sol";
diff --git a/test/Common.t.sol b/test/Common.t.sol
index f4dc31f..ccef8f6 100644
--- a/test/Common.t.sol
+++ b/test/Common.t.sol
@@ -1,20 +1,4 @@
-// This file is part of Darwinia.
-// Copyright (C) 2018-2023 Darwinia Network
-// SPDX-License-Identifier: GPL-3.0
-//
-// Darwinia 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.
-//
-// Darwinia 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 Darwinia. If not, see <https://www.gnu.org/licenses/>.
-
+// SPDX-License-Identifier: MIT
 pragma solidity 0.8.17;
 
 import "forge-std/Test.sol";
diff --git a/test/ORMP.m.sol b/test/ORMP.m.sol
index c0be4fe..e5c2740 100644
--- a/test/ORMP.m.sol
+++ b/test/ORMP.m.sol
@@ -1,20 +1,4 @@
-// This file is part of Darwinia.
-// Copyright (C) 2018-2023 Darwinia Network
-// SPDX-License-Identifier: GPL-3.0
-//
-// Darwinia 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.
-//
-// Darwinia 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 Darwinia. If not, see <https://www.gnu.org/licenses/>.
-
+// SPDX-License-Identifier: MIT
 pragma solidity 0.8.17;
 
 import "../src/ORMP.sol";
diff --git a/test/ORMP.t.sol b/test/ORMP.t.sol
index 8d1d2e0..46a7654 100644
--- a/test/ORMP.t.sol
+++ b/test/ORMP.t.sol
@@ -1,20 +1,4 @@
-// This file is part of Darwinia.
-// Copyright (C) 2018-2023 Darwinia Network
-// SPDX-License-Identifier: GPL-3.0
-//
-// Darwinia 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.
-//
-// Darwinia 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 Darwinia. If not, see <https://www.gnu.org/licenses/>.
-
+// SPDX-License-Identifier: MIT
 pragma solidity 0.8.17;
 
 import "forge-std/Test.sol";
diff --git a/test/UserConfig.t.sol b/test/UserConfig.t.sol
index 01b5df8..017ccd4 100644
--- a/test/UserConfig.t.sol
+++ b/test/UserConfig.t.sol
@@ -1,20 +1,4 @@
-// This file is part of Darwinia.
-// Copyright (C) 2018-2023 Darwinia Network
-// SPDX-License-Identifier: GPL-3.0
-//
-// Darwinia 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.
-//
-// Darwinia 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 Darwinia. If not, see <https://www.gnu.org/licenses/>.
-
+// SPDX-License-Identifier: MIT
 pragma solidity 0.8.17;
 
 import "forge-std/Test.sol";
diff --git a/test/bench/ORMP.b.sol b/test/bench/ORMP.b.sol
index 7e69457..8f49c7a 100644
--- a/test/bench/ORMP.b.sol
+++ b/test/bench/ORMP.b.sol
@@ -1,20 +1,4 @@
-// This file is part of Darwinia.
-// Copyright (C) 2018-2023 Darwinia Network
-// SPDX-License-Identifier: GPL-3.0
-//
-// Darwinia 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.
-//
-// Darwinia 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 Darwinia. If not, see <https://www.gnu.org/licenses/>.
-
+// SPDX-License-Identifier: MIT
 pragma solidity 0.8.17;
 
 import "forge-std/Test.sol";
diff --git a/test/eco/Oracle.t.sol b/test/eco/Oracle.t.sol
index 3174e02..7745cfb 100644
--- a/test/eco/Oracle.t.sol
+++ b/test/eco/Oracle.t.sol
@@ -1,20 +1,4 @@
-// This file is part of Darwinia.
-// Copyright (C) 2018-2023 Darwinia Network
-// SPDX-License-Identifier: GPL-3.0
-//
-// Darwinia 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.
-//
-// Darwinia 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 Darwinia. If not, see <https://www.gnu.org/licenses/>.
-
+// SPDX-License-Identifier: MIT
 pragma solidity 0.8.17;
 
 import "forge-std/Test.sol";
diff --git a/test/eco/Relayer.t.sol b/test/eco/Relayer.t.sol
index 6b10006..62de712 100644
--- a/test/eco/Relayer.t.sol
+++ b/test/eco/Relayer.t.sol
@@ -1,20 +1,4 @@
-// This file is part of Darwinia.
-// Copyright (C) 2018-2023 Darwinia Network
-// SPDX-License-Identifier: GPL-3.0
-//
-// Darwinia 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.
-//
-// Darwinia 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 Darwinia. If not, see <https://www.gnu.org/licenses/>.
-
+// SPDX-License-Identifier: MIT
 pragma solidity 0.8.17;
 
 import "forge-std/Test.sol";
diff --git a/test/security/ExcessivelySafeCall.t.sol b/test/security/ExcessivelySafeCall.t.sol
index d4fe93d..3152212 100644
--- a/test/security/ExcessivelySafeCall.t.sol
+++ b/test/security/ExcessivelySafeCall.t.sol
@@ -1,20 +1,4 @@
-// This file is part of Darwinia.
-// Copyright (C) 2018-2023 Darwinia Network
-// SPDX-License-Identifier: GPL-3.0
-//
-// Darwinia 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.
-//
-// Darwinia 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 Darwinia. If not, see <https://www.gnu.org/licenses/>.
-
+// SPDX-License-Identifier: MIT
 pragma solidity >=0.8.17;
 
 import "forge-std/Test.sol";
diff --git a/test/user/Application.t.sol b/test/user/Application.t.sol
index 68784d5..1c8d9aa 100644
--- a/test/user/Application.t.sol
+++ b/test/user/Application.t.sol
@@ -1,20 +1,4 @@
-// This file is part of Darwinia.
-// Copyright (C) 2018-2023 Darwinia Network
-// SPDX-License-Identifier: GPL-3.0
-//
-// Darwinia 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.
-//
-// Darwinia 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 Darwinia. If not, see <https://www.gnu.org/licenses/>.
-
+// SPDX-License-Identifier: MIT
 pragma solidity 0.8.17;
 
 import "forge-std/Test.sol";