diff --git a/src/Greenfield/Protobuf/.gitignore b/src/Greenfield/Protobuf/.gitignore
new file mode 100644
index 00000000000..c96d61208c0
--- /dev/null
+++ b/src/Greenfield/Protobuf/.gitignore
@@ -0,0 +1,3 @@
+*.cc
+*.h
+
diff --git a/src/Greenfield/SignerEip712.cpp b/src/Greenfield/SignerEip712.cpp
index dc7a1d7d794..7cf6a231ed0 100644
--- a/src/Greenfield/SignerEip712.cpp
+++ b/src/Greenfield/SignerEip712.cpp
@@ -7,6 +7,8 @@
 #include "SignerEip712.h"
 
 #include "Ethereum/MessageSigner.h"
+#include "Ethereum/ABI/ParamStruct.h"
+#include "HexCoding.h"
 
 #include <unordered_map>
 
@@ -160,7 +162,18 @@ json SignerEip712::wrapTxToTypedData(const Proto::SigningInput& input) {
     }
 }
 
+Data SignerEip712::preImageHash(const Proto::SigningInput& input) {
+    const auto txTypedData = wrapTxToTypedData(input);
+    return Ethereum::ABI::ParamStruct::hashStructJson(txTypedData.dump());
+}
+
 Data SignerEip712::sign(const Proto::SigningInput& input) {
+    const PrivateKey privateKey(data(input.private_key()));
+    const auto txTypedData = wrapTxToTypedData(input).dump();
+    const auto chainId = std::stoull(input.eth_chain_id());
+
+    const auto signatureStr = Ethereum::MessageSigner::signTypedData(privateKey, txTypedData, Ethereum::MessageType::Legacy, chainId);
+    return parse_hex(signatureStr);
 }
 
 } // namespace TW::Greenfield
diff --git a/src/Greenfield/SignerEip712.h b/src/Greenfield/SignerEip712.h
index 94b73198b6b..aef94542b88 100644
--- a/src/Greenfield/SignerEip712.h
+++ b/src/Greenfield/SignerEip712.h
@@ -23,6 +23,9 @@ class SignerEip712 {
     /// Returns an rsv signature.
     static Data sign(const Proto::SigningInput& input);
 
+    /// Returns a pre-image hash that needs to be signed.
+    static Data preImageHash(const Proto::SigningInput& input);
+
     /// Packs the Tx input in a EIP712 object.
     static json wrapTxToTypedData(const Proto::SigningInput& input);
 
diff --git a/tests/chains/Greenfield/SignerTests.cpp b/tests/chains/Greenfield/SignerTests.cpp
index 56d8cc79cf5..353fdfaffec 100644
--- a/tests/chains/Greenfield/SignerTests.cpp
+++ b/tests/chains/Greenfield/SignerTests.cpp
@@ -14,7 +14,7 @@
 
 namespace TW::Greenfield::tests {
 
-TEST(GreenfieldSigner, Eip712TypedDataJson) {
+TEST(GreenfieldSigner, SignerEip712) {
     Proto::SigningInput input;
     input.set_signing_mode(Proto::Eip712);
     input.set_account_number(15560);
@@ -36,8 +36,8 @@ TEST(GreenfieldSigner, Eip712TypedDataJson) {
     amountOfFee->set_denom("BNB");
     amountOfFee->set_amount("2000000000000000");
 
-    auto actual = SignerEip712::wrapTxToTypedData(input);
-    auto expected = json::parse(R"(
+    auto typedData = SignerEip712::wrapTxToTypedData(input);
+    auto expectedJson = json::parse(R"(
 {
     "types": {
         "Coin": [
@@ -188,7 +188,18 @@ TEST(GreenfieldSigner, Eip712TypedDataJson) {
     }
 }
     )");
-    EXPECT_EQ(actual, expected);
+    EXPECT_EQ(typedData, expectedJson);
+
+    auto expectedPreHash = "b8c62654582ca96b37ca94966199682bf70ed934e740d2f874ff54675a0ac344";
+    auto preHash = SignerEip712::preImageHash(input);
+    EXPECT_EQ(hex(preHash), expectedPreHash);
+
+    auto privateKey = parse_hex("9066aa168c379a403becb235c15e7129c133c244e56a757ab07bc369288bcab0");
+    input.set_private_key(privateKey.data(), privateKey.size());
+
+    auto signature = SignerEip712::sign(input);
+    auto expectedSignature = "cb3a4684a991014a387a04a85b59227ebb79567c2025addcb296b4ca856e9f810d3b526f2a0d0fad6ad1b126b3b9516f8b3be020a7cca9c03ce3cf47f4199b6d1b";
+    EXPECT_EQ(hex(signature), expectedSignature);
 }
 
 } // namespace TW::Greenfield::tests