diff --git a/rskj-core/src/test/java/co/rsk/peg/RegisterBtcTransactionIT.java b/rskj-core/src/test/java/co/rsk/peg/RegisterBtcTransactionIT.java
index 1f7ed3484c..38dbf100d2 100644
--- a/rskj-core/src/test/java/co/rsk/peg/RegisterBtcTransactionIT.java
+++ b/rskj-core/src/test/java/co/rsk/peg/RegisterBtcTransactionIT.java
@@ -120,7 +120,7 @@ void registerBtcTransaction_forALegacyBtcTransaction_shouldRegisterTheNewUtxoAnd
 
         int outputIndex = 0;
         TransactionOutput output = bitcoinTransaction.getOutput(outputIndex);
-        List<UTXO> expectedFederationUtxos = Collections.singletonList(utxoOf(bitcoinTransaction, output));
+        List<UTXO> expectedFederationUtxos = List.of(utxoOf(bitcoinTransaction, output));
         assertEquals(expectedFederationUtxos, federationSupport.getActiveFederationBtcUTXOs());
 
         co.rsk.core.Coin expectedReceiverBalance = co.rsk.core.Coin.fromBitcoin(output.getValue());
@@ -136,7 +136,7 @@ void registerBtcTransaction_forARepeatedLegacyBtcTransaction_shouldNotPerformAny
         bridgeSupport.save();
 
         co.rsk.core.Coin expectedReceiverBalance = repository.getBalance(rskReceiver);
-        List<UTXO> expectedFederationUTXOs = federationSupport.getActiveFederationBtcUTXOs();
+        List<UTXO> expectedFederationUTXOs = List.copyOf(federationSupport.getActiveFederationBtcUTXOs());
 
         // Act
         bridgeSupport.registerBtcTransaction(rskTx, bitcoinTransaction.bitcoinSerialize(), btcBlockWithPmtHeight, pmtWithTransactions.bitcoinSerialize());
@@ -147,12 +147,29 @@ void registerBtcTransaction_forARepeatedLegacyBtcTransaction_shouldNotPerformAny
         assertEquals(expectedReceiverBalance, repository.getBalance(rskReceiver));
     }
 
+    @Test
+    void registerBtcTransaction_whenLegacyBtcTransactionWithNegativeHeight_shouldNotPerformAnyChange() throws Exception {
+        // Arrange
+        co.rsk.core.Coin expectedReceiverBalance = repository.getBalance(rskReceiver);
+        List<UTXO> expectedFederationUTXOs = List.copyOf(federationSupport.getActiveFederationBtcUTXOs());
+
+        // Act
+        int height = -1;
+        bridgeSupport.registerBtcTransaction(rskTx, bitcoinTransaction.bitcoinSerialize(), height, pmtWithTransactions.bitcoinSerialize());
+        bridgeSupport.save();
+
+        // Assert
+        assertEquals(expectedFederationUTXOs, federationSupport.getActiveFederationBtcUTXOs());
+        assertEquals(expectedReceiverBalance, repository.getBalance(rskReceiver));
+    }
+
     private static UTXO utxoOf(BtcTransaction bitcoinTransaction, TransactionOutput output) {
+        int height = 0;
         return new UTXO(
             bitcoinTransaction.getHash(),
             output.getIndex(),
             output.getValue(),
-            0,
+            height,
             bitcoinTransaction.isCoinBase(),
             output.getScriptPubKey()
         );
@@ -160,7 +177,9 @@ private static UTXO utxoOf(BtcTransaction bitcoinTransaction, TransactionOutput
 
     private BtcTransaction createPegInTransaction(Address federationAddress, Coin coin, BtcECKey pubKey) {
         BtcTransaction btcTx = new BtcTransaction(btcNetworkParams);
-        btcTx.addInput(BitcoinTestUtils.createHash(0), 0, ScriptBuilder.createInputScript(null, pubKey));
+        int outputIndex = 0;
+        int nHash = 0;
+        btcTx.addInput(BitcoinTestUtils.createHash(nHash), outputIndex, ScriptBuilder.createInputScript(null, pubKey));
         btcTx.addOutput(new TransactionOutput(btcNetworkParams, btcTx, coin, federationAddress));
 
         return btcTx;
@@ -169,7 +188,8 @@ private BtcTransaction createPegInTransaction(Address federationAddress, Coin co
     private void assertLogPegInBtc() {
         Sha256Hash peginTransactionHash = bitcoinTransaction.getHash();
         List<DataWord> encodedTopics = getEncodedTopics(BridgeEvents.PEGIN_BTC.getEvent(), rskReceiver.toString(), peginTransactionHash.getBytes());
-        byte[] encodedData = getEncodedData(BridgeEvents.PEGIN_BTC.getEvent(), minimumPeginValue.getValue(), 0);
+        int protocolVersion = 0;
+        byte[] encodedData = getEncodedData(BridgeEvents.PEGIN_BTC.getEvent(), minimumPeginValue.getValue(), protocolVersion);
 
         assertEventWasEmittedWithExpectedTopics(encodedTopics, logs);
         assertEventWasEmittedWithExpectedData(encodedData, logs);