diff --git a/ApplicationLibCode/FileInterface/RifSummaryReaderInterface.cpp b/ApplicationLibCode/FileInterface/RifSummaryReaderInterface.cpp
index 51c9be4541..5abb2280e1 100644
--- a/ApplicationLibCode/FileInterface/RifSummaryReaderInterface.cpp
+++ b/ApplicationLibCode/FileInterface/RifSummaryReaderInterface.cpp
@@ -69,12 +69,20 @@ int RifSummaryReaderInterface::serialNumber() const
 //--------------------------------------------------------------------------------------------------
 ///
 //--------------------------------------------------------------------------------------------------
-RifSummaryReaderInterface::RifSummaryReaderInterface()
+void RifSummaryReaderInterface::increaseSerialNumber()
 {
 #pragma omp critical
     m_serialNumber = m_nextSerialNumber++;
 }
 
+//--------------------------------------------------------------------------------------------------
+///
+//--------------------------------------------------------------------------------------------------
+RifSummaryReaderInterface::RifSummaryReaderInterface()
+{
+    increaseSerialNumber();
+}
+
 //--------------------------------------------------------------------------------------------------
 ///
 //--------------------------------------------------------------------------------------------------
diff --git a/ApplicationLibCode/FileInterface/RifSummaryReaderInterface.h b/ApplicationLibCode/FileInterface/RifSummaryReaderInterface.h
index 2f86ae86af..cee40c9d22 100644
--- a/ApplicationLibCode/FileInterface/RifSummaryReaderInterface.h
+++ b/ApplicationLibCode/FileInterface/RifSummaryReaderInterface.h
@@ -58,6 +58,8 @@ class RifSummaryReaderInterface : public cvf::Object
     int serialNumber() const;
 
 protected:
+    void increaseSerialNumber();
+
     std::set<RifEclipseSummaryAddress> m_allResultAddresses; // Result and error addresses
     std::set<RifEclipseSummaryAddress> m_allErrorAddresses; // Error addresses
 
diff --git a/ApplicationLibCode/ProjectDataModel/Summary/Sumo/RimSummaryCaseSumo.cpp b/ApplicationLibCode/ProjectDataModel/Summary/Sumo/RimSummaryCaseSumo.cpp
index 9676dbacb0..6220ea82db 100644
--- a/ApplicationLibCode/ProjectDataModel/Summary/Sumo/RimSummaryCaseSumo.cpp
+++ b/ApplicationLibCode/ProjectDataModel/Summary/Sumo/RimSummaryCaseSumo.cpp
@@ -124,6 +124,8 @@ void RimSummaryCaseSumo::setValues( const std::vector<time_t>&      timeSteps,
 {
     m_timeSteps             = timeSteps;
     m_values[resultAddress] = values;
+
+    increaseSerialNumber();
 }
 
 //--------------------------------------------------------------------------------------------------