diff --git a/core/state/state_object.go b/core/state/state_object.go
index 66a9e7b865..8489a18382 100644
--- a/core/state/state_object.go
+++ b/core/state/state_object.go
@@ -375,11 +375,11 @@ func (s *stateObject) updateRoot() {
 // commit obtains a set of dirty storage trie nodes and updates the account data.
 // The returned set can be nil if nothing to commit. This function assumes all
 // storage mutations have already been flushed into trie by updateRoot.
-func (s *stateObject) commit() (*trienode.NodeSet, error) {
+func (s *stateObject) commit() (*trienode.NodeSet, *trienode.Witness, error) {
 	// Short circuit if trie is not even loaded, don't bother with committing anything
 	if s.trie == nil {
 		s.origin = s.data.Copy()
-		return nil, nil
+		return nil, nil, nil
 	}
 	// Track the amount of time wasted on committing the storage trie
 	if metrics.EnabledExpensive {
@@ -388,15 +388,15 @@ func (s *stateObject) commit() (*trienode.NodeSet, error) {
 	// The trie is currently in an open state and could potentially contain
 	// cached mutations. Call commit to acquire a set of nodes that have been
 	// modified, the set can be nil if nothing to commit.
-	root, nodes, _, err := s.trie.Commit(false)
+	root, nodes, witness, err := s.trie.Commit(false)
 	if err != nil {
-		return nil, err
+		return nil, nil, err
 	}
 	s.data.Root = root
 
 	// Update original account data after commit
 	s.origin = s.data.Copy()
-	return nodes, nil
+	return nodes, witness, nil
 }
 
 // AddBalance adds amount to s's balance.
diff --git a/core/state/statedb.go b/core/state/statedb.go
index e26ab92d7e..8781144941 100644
--- a/core/state/statedb.go
+++ b/core/state/statedb.go
@@ -1177,6 +1177,7 @@ func (s *StateDB) Commit(block uint64, deleteEmptyObjects bool) (common.Hash, er
 		storageTrieNodesUpdated int
 		storageTrieNodesDeleted int
 		nodes                   = trienode.NewMergedNodeSet()
+		witnesses               = trienode.NewWitnesses()
 		codeWriter              = s.db.DiskDB().NewBatch()
 	)
 	// Handle all state deletions first
@@ -1196,7 +1197,7 @@ func (s *StateDB) Commit(block uint64, deleteEmptyObjects bool) (common.Hash, er
 			obj.dirtyCode = false
 		}
 		// Write any storage changes in the state object to its storage trie
-		set, err := obj.commit()
+		set, witness, err := obj.commit()
 		if err != nil {
 			return common.Hash{}, err
 		}
@@ -1211,6 +1212,9 @@ func (s *StateDB) Commit(block uint64, deleteEmptyObjects bool) (common.Hash, er
 			storageTrieNodesUpdated += updates
 			storageTrieNodesDeleted += deleted
 		}
+		if witness != nil {
+			witnesses.Merge(witness)
+		}
 	}
 	if codeWriter.ValueSize() > 0 {
 		if err := codeWriter.Write(); err != nil {
@@ -1222,7 +1226,7 @@ func (s *StateDB) Commit(block uint64, deleteEmptyObjects bool) (common.Hash, er
 	if metrics.EnabledExpensive {
 		start = time.Now()
 	}
-	root, set, _, err := s.trie.Commit(true)
+	root, set, witness, err := s.trie.Commit(true)
 	if err != nil {
 		return common.Hash{}, err
 	}
@@ -1233,6 +1237,9 @@ func (s *StateDB) Commit(block uint64, deleteEmptyObjects bool) (common.Hash, er
 		}
 		accountTrieNodesUpdated, accountTrieNodesDeleted = set.Size()
 	}
+	if witness != nil {
+		witnesses.Merge(witness)
+	}
 	if metrics.EnabledExpensive {
 		s.AccountCommits += time.Since(start)
 
diff --git a/trie/trienode/witness.go b/trie/trienode/witness.go
index ba16bdc5f8..ac328a3f15 100644
--- a/trie/trienode/witness.go
+++ b/trie/trienode/witness.go
@@ -59,3 +59,24 @@ func (w *Witness) Copy() *Witness {
 	}
 	return cpy
 }
+
+// Witnesses represents a set of witness for a group of tries.
+type Witnesses struct {
+	witness map[common.Hash]*Witness
+}
+
+// NewWitnesses initializes an empty witness set.
+func NewWitnesses() *Witnesses {
+	return &Witnesses{witness: make(map[common.Hash]*Witness)}
+}
+
+// Merge merges the provided dirty nodes of a trie into the set. The assumption
+// is held that no duplicated set belonging to the same trie will be merged twice.
+func (set *Witnesses) Merge(other *Witness) error {
+	_, present := set.witness[other.Owner]
+	if present {
+		//return subset.Merge(other.Owner, other.Nodes)
+	}
+	set.witness[other.Owner] = other
+	return nil
+}