diff --git a/test/helpers/WitnetRequestBoardTrojanHorseBadProxiable.sol b/test/helpers/WitnetRequestBoardTrojanHorseBadProxiable.sol
index 93f6ac71b..88cafe84b 100644
--- a/test/helpers/WitnetRequestBoardTrojanHorseBadProxiable.sol
+++ b/test/helpers/WitnetRequestBoardTrojanHorseBadProxiable.sol
@@ -38,7 +38,7 @@ contract WitnetRequestBoardTrojanHorseBadProxiable is Initializable, Proxiable {
     }
   }
 
-  function initialize(bytes calldata) external override {
+  function initialize(bytes calldata) external {
       // WATCH OUT: any one could reset storage context after 
       // upgrading the WRB to this implementation.
   }
diff --git a/test/helpers/WitnetRequestBoardTrojanHorseNotUpgradable.sol b/test/helpers/WitnetRequestBoardTrojanHorseNotUpgradable.sol
index 92f391995..25ee71d4a 100644
--- a/test/helpers/WitnetRequestBoardTrojanHorseNotUpgradable.sol
+++ b/test/helpers/WitnetRequestBoardTrojanHorseNotUpgradable.sol
@@ -37,7 +37,7 @@ contract WitnetRequestBoardTrojanHorseNotUpgradable is Initializable, Proxiable
     }
   }
 
-  function initialize(bytes calldata) external override {
+  function initialize(bytes calldata) external {
       // WATCH OUT: any one could reset storage context after 
       // upgrading the WRB to this implementation.
   }