diff --git a/src/main/java/org/qortal/arbitrary/ArbitraryDataCombiner.java b/src/main/java/org/qortal/arbitrary/ArbitraryDataCombiner.java
index ccbfb85c..681a5949 100644
--- a/src/main/java/org/qortal/arbitrary/ArbitraryDataCombiner.java
+++ b/src/main/java/org/qortal/arbitrary/ArbitraryDataCombiner.java
@@ -4,6 +4,7 @@ import org.apache.commons.io.FileUtils;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.qortal.arbitrary.metadata.ArbitraryDataMetadataPatch;
+import org.qortal.utils.Base58;
 import org.qortal.utils.FilesystemUtils;
 
 import java.io.File;
@@ -32,6 +33,7 @@ public class ArbitraryDataCombiner {
         try {
             this.preExecute();
             this.validatePreviousSignature();
+            this.validatePreviousHash();
             this.process();
 
         } finally {
@@ -101,6 +103,24 @@ public class ArbitraryDataCombiner {
         }
     }
 
+    private void validatePreviousHash() throws IOException {
+        ArbitraryDataMetadataPatch metadata = new ArbitraryDataMetadataPatch(this.pathAfter);
+        metadata.read();
+        byte[] previousHash = metadata.getPreviousHash();
+        if (previousHash == null) {
+            throw new IllegalStateException("Unable to extract previous hash from patch metadata");
+        }
+
+        ArbitraryDataDigest digest = new ArbitraryDataDigest(this.pathBefore);
+        digest.compute();
+        boolean valid = digest.isHashValid(previousHash);
+        if (!valid) {
+            String previousHash58 = Base58.encode(previousHash);
+            throw new IllegalStateException(String.format("Previous state hash mismatch. " +
+                    "Patch prevHash: %s, actual: %s", previousHash58, digest.getHash58()));
+        }
+    }
+
     private void process() throws IOException {
         ArbitraryDataMerge merge = new ArbitraryDataMerge(this.pathBefore, this.pathAfter);
         merge.compute();