diff --git a/core/contracts/Litmus.sol b/core/contracts/Litmus.sol
index 8eb0b9ade..42fb2bab7 100644
--- a/core/contracts/Litmus.sol
+++ b/core/contracts/Litmus.sol
@@ -1,4 +1,4 @@
-// SPDX-License-Identifier: UNLICENSED
+// SPDX-License-Identifier: GPL-3.0-only
 pragma solidity ^0.8.9;
 
 // Uncomment this line to use console.log