diff --git a/src/Mod/Spreadsheet/App/SpreadsheetExpression.cpp b/src/Mod/Spreadsheet/App/SpreadsheetExpression.cpp
index 807ed22d2..a25199624 100644
--- a/src/Mod/Spreadsheet/App/SpreadsheetExpression.cpp
+++ b/src/Mod/Spreadsheet/App/SpreadsheetExpression.cpp
@@ -87,6 +87,19 @@ AggregateFunctionExpression::~AggregateFunctionExpression()
 {
 }
 
+Expression *AggregateFunctionExpression::copy() const
+{
+    std::vector<Expression*>::const_iterator i = args.begin();
+    std::vector<Expression*> a;
+
+    while (i != args.end()) {
+        a.push_back((*i)->copy());
+        ++i;
+    }
+
+    return new AggregateFunctionExpression(owner, f, a);
+}
+
 /**
   * Evaluate function. Returns a NumberExpression if evaluation is successfuly.
   * Throws an exception if something fails.
diff --git a/src/Mod/Spreadsheet/App/SpreadsheetExpression.h b/src/Mod/Spreadsheet/App/SpreadsheetExpression.h
index a7f0be912..d2848cd87 100644
--- a/src/Mod/Spreadsheet/App/SpreadsheetExpression.h
+++ b/src/Mod/Spreadsheet/App/SpreadsheetExpression.h
@@ -90,6 +90,8 @@ public:
 
     virtual ~AggregateFunctionExpression();
 
+    virtual Expression * copy() const;
+
     virtual App::Expression * eval() const;
 
     virtual std::string toString() const;