If you are binding the grids directly to the data source, then this is quite normal behavior. What I suggest you do is bind each grid to separate DataGridCollectionViews, which are in turn bound to the same data source. For example:
DataGridCollectionView view1 = new DataGridCollectionView( myFilteredMiniFutureCollection );
DataGridCollectionView view21 = new DataGridCollectionView( myFilteredMiniFutureCollection );
dataGridControl1.ItemsSource = view1
dataGridControl2.ItemsSource = view2;
Technical Writer - Xceed Software
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