1 files changed, 10 insertions, 6 deletions
diff --git a/packages/contracts/src/2.0.0/protocol/Exchange/MixinTransactions.sol b/packages/contracts/src/2.0.0/protocol/Exchange/MixinTransactions.sol
index 88d2da7d7..b5de1a5de 100644
--- a/packages/contracts/src/2.0.0/protocol/Exchange/MixinTransactions.sol
+++ b/packages/contracts/src/2.0.0/protocol/Exchange/MixinTransactions.sol
@@ -123,19 +123,23 @@ contract MixinTransactions is
         bytes32 dataHash = keccak256(data);
 
         // Assembly for more efficiently computing:
-        // keccak256(abi.encode(
+        // keccak256(abi.encodePacked(
         //     EIP712_ZEROEX_TRANSACTION_SCHEMA_HASH,
         //     salt,
-        //     signerAddress,
+        //     bytes32(signerAddress),
         //     keccak256(data)
         // ));
 
         assembly {
+            // Load free memory pointer
             let memPtr := mload(64)
-            mstore(memPtr, schemaHash)
-            mstore(add(memPtr, 32), salt)
-            mstore(add(memPtr, 64), and(signerAddress, 0xffffffffffffffffffffffffffffffffffffffff))
-            mstore(add(memPtr, 96), dataHash)
+
+            mstore(memPtr, schemaHash)                                                               // hash of schema
+            mstore(add(memPtr, 32), salt)                                                            // salt
+            mstore(add(memPtr, 64), and(signerAddress, 0xffffffffffffffffffffffffffffffffffffffff))  // signerAddress
+            mstore(add(memPtr, 96), dataHash)                                                        // hash of data
+
+            // Compute hash
             result := keccak256(memPtr, 128)
         }