Use ITopologicalOperator4::Simplify method to simplify the geometries.To test the workaround uncomment following lines from the ContainsTestCmd.cs file.ITopologicalOperator4 pTopologicalOp = (ITopologicalOperator4)largePolyFeature.Shape;pTopologicalOp.IsKnownSimple_2 = false;pTopologicalOp.Simplify();ITopologicalOperator4 pTopoOp2 = (ITopologicalOperator4)smallPolyFeature.Shape;pTopoOp2.IsKnownSimple_2 = false;pTopoOp2.Simplify();