diff --git a/v2/storagegroup/convert.go b/v2/storagegroup/convert.go
index df545f92..67126197 100644
--- a/v2/storagegroup/convert.go
+++ b/v2/storagegroup/convert.go
@@ -15,7 +15,9 @@ func StorageGroupToGRPCMessage(s *StorageGroup) *sg.StorageGroup {
 	m := new(sg.StorageGroup)
 
 	m.SetValidationDataSize(s.GetValidationDataSize())
-	m.SetValidationHash(s.GetValidationHash())
+	m.SetValidationHash(
+		refs.ChecksumToGRPCMessage(s.GetValidationHash()),
+	)
 	m.SetExpirationEpoch(s.GetExpirationEpoch())
 
 	members := s.GetMembers()
@@ -39,7 +41,9 @@ func StorageGroupFromGRPCMessage(m *sg.StorageGroup) *StorageGroup {
 	s := new(StorageGroup)
 
 	s.SetValidationDataSize(m.GetValidationDataSize())
-	s.SetValidationHash(m.GetValidationHash())
+	s.SetValidationHash(
+		refs.ChecksumFromGRPCMessage(m.GetValidationHash()),
+	)
 	s.SetExpirationEpoch(m.GetExpirationEpoch())
 
 	memberMsg := m.GetMembers()
diff --git a/v2/storagegroup/grpc/types.go b/v2/storagegroup/grpc/types.go
index b1159c48..5bba1b15 100644
--- a/v2/storagegroup/grpc/types.go
+++ b/v2/storagegroup/grpc/types.go
@@ -12,7 +12,7 @@ func (m *StorageGroup) SetValidationDataSize(v uint64) {
 }
 
 // SetValidationHash sets total homomorphic hash of the storage group payloads.
-func (m *StorageGroup) SetValidationHash(v []byte) {
+func (m *StorageGroup) SetValidationHash(v *refs.Checksum) {
 	if m != nil {
 		m.ValidationHash = v
 	}
diff --git a/v2/storagegroup/marshal.go b/v2/storagegroup/marshal.go
index cc1160f7..33b0c155 100644
--- a/v2/storagegroup/marshal.go
+++ b/v2/storagegroup/marshal.go
@@ -34,7 +34,7 @@ func (s *StorageGroup) StableMarshal(buf []byte) ([]byte, error) {
 
 	offset += n
 
-	n, err = proto.BytesMarshal(hashField, buf[offset:], s.hash)
+	n, err = proto.NestedStructureMarshal(hashField, buf[offset:], s.hash)
 	if err != nil {
 		return nil, err
 	}
@@ -67,7 +67,7 @@ func (s *StorageGroup) StableSize() (size int) {
 	}
 
 	size += proto.UInt64Size(sizeField, s.size)
-	size += proto.BytesSize(hashField, s.hash)
+	size += proto.NestedStructureSize(hashField, s.hash)
 	size += proto.UInt64Size(expirationField, s.exp)
 
 	for i := range s.members {
diff --git a/v2/storagegroup/marshal_test.go b/v2/storagegroup/marshal_test.go
index b79ed80c..0b6a1919 100644
--- a/v2/storagegroup/marshal_test.go
+++ b/v2/storagegroup/marshal_test.go
@@ -21,7 +21,7 @@ func TestStorageGroup_StableMarshal(t *testing.T) {
 
 	t.Run("non empty", func(t *testing.T) {
 		storageGroupFrom.SetValidationDataSize(300)
-		storageGroupFrom.SetValidationHash([]byte("Homomorphic hash value"))
+		storageGroupFrom.SetValidationHash(generateChecksum("Homomorphic hash"))
 		storageGroupFrom.SetExpirationEpoch(100)
 		storageGroupFrom.SetMembers([]*refs.ObjectID{ownerID1, ownerID2})
 
@@ -35,3 +35,11 @@ func TestStorageGroup_StableMarshal(t *testing.T) {
 		require.Equal(t, storageGroupFrom, storageGroupTo)
 	})
 }
+
+func generateChecksum(data string) *refs.Checksum {
+	checksum := new(refs.Checksum)
+	checksum.SetType(refs.TillichZemor)
+	checksum.SetSum([]byte(data))
+
+	return checksum
+}
diff --git a/v2/storagegroup/types.go b/v2/storagegroup/types.go
index 720bbe14..6c493ed0 100644
--- a/v2/storagegroup/types.go
+++ b/v2/storagegroup/types.go
@@ -9,7 +9,7 @@ import (
 type StorageGroup struct {
 	size uint64
 
-	hash []byte
+	hash *refs.Checksum
 
 	exp uint64
 
@@ -33,7 +33,7 @@ func (s *StorageGroup) SetValidationDataSize(v uint64) {
 }
 
 // GetValidationHash of unified storage group structure.
-func (s *StorageGroup) GetValidationHash() []byte {
+func (s *StorageGroup) GetValidationHash() *refs.Checksum {
 	if s != nil {
 		return s.hash
 	}
@@ -42,7 +42,7 @@ func (s *StorageGroup) GetValidationHash() []byte {
 }
 
 // SetValidationHash into unified storage group structure.
-func (s *StorageGroup) SetValidationHash(v []byte) {
+func (s *StorageGroup) SetValidationHash(v *refs.Checksum) {
 	if s != nil {
 		s.hash = v
 	}