<telerik:GridViewDataColumn Width="100"
		DataMemberBinding="{Binding YearRange}"
		Header="Årgang">
	<telerik:GridViewDataColumn.FilteringControl>
		<local:CustomGridFilter Aargang="{Binding ElementName=root, Path=VintageYear, Mode=TwoWay}" />
	</telerik:GridViewDataColumn.FilteringControl>
</telerik:GridViewDataColumn>

public class YearRange : IEquatable<int>
{
    public int FromYear { get; set; }

    public int ToYear { get; set; }

    public int Year { get; set; }

    public override string ToString()
    {
        if (FromYear == ToYear)
            return FromYear.ToString();

        return FromYear + "-" + ToYear;
    }

  #region Equals, GetHashCode

  #region Comparison operators override
}

public partial class CustomGridFilter : UserControl, IFilteringControl, INotifyPropertyChanged
{
    private GridViewBoundColumnBase column;
    private CompositeFilterDescriptor compositeFilter;
    private FilterDescriptor rangeFilter;

    #region INotifyPropertyChanged

    public void OnPropertyChanged(string name) => PropertyChanged?.Invoke(this, new PropertyChangedEventArgs(name));

    public event PropertyChangedEventHandler PropertyChanged;

    #endregion

    #region IsActive DependencyProperty 
    public bool IsActive
    {
        get { return (bool)GetValue(IsActiveProperty); }
        set { SetValue(IsActiveProperty, value); }
    }

    public static readonly DependencyProperty IsActiveProperty =
        DependencyProperty.Register(
            "IsActive",
            typeof(bool),
            typeof(CustomGridFilter),
            new PropertyMetadata(false));
    #endregion

    #region Aargang DependencyProperty 

    public int? Aargang
    {
        get { return (int?)GetValue(AargangProperty); }
        set { SetValue(AargangProperty, value); }
    }

    public static readonly DependencyProperty AargangProperty =
        DependencyProperty.Register(
            "Aargang",
            typeof(int?),
            typeof(CustomGridFilter),
            new PropertyMetadata(
                null,
                (sender, evt) => { ((CustomGridFilter)sender).OnPropertyChanged("Aargang"); }
            )
        );

    #endregion

    public CustomGridFilter()
    {
        InitializeComponent();

        DataContext = this;

        PropertyChanged += CustomGridFilter_PropertyChanged;
    }

    private void CustomGridFilter_PropertyChanged(object sender, PropertyChangedEventArgs e)
    {
        if (e.PropertyName == "Aargang" && Aargang>1900 && Aargang<2100)
        {
            OnFilter(null, null);
        }
    }

    public void Prepare(Telerik.Windows.Controls.GridViewColumn column)
    {
        this.column = column as GridViewBoundColumnBase;

        if (this.column == null)
        {
            return;
        }

        if (compositeFilter == null)
        {
            CreateFilters();
        }
    }

    private void CreateFilters()
    {
        string dataMember = column.DataMemberBinding.Path.Path;

        compositeFilter = new CompositeFilterDescriptor();

        rangeFilter = new FilterDescriptor(dataMember, FilterOperator.IsEqualTo, null);

        compositeFilter.FilterDescriptors.Add(rangeFilter);
    }

    private void OnFilter(object sender, RoutedEventArgs e)
    {
        rangeFilter.Value = new YearRange { Year = Aargang ?? 0 };

        if (!column.DataControl.FilterDescriptors.Contains(compositeFilter))
        {
            column.DataControl.FilterDescriptors.Add(compositeFilter);
        }

        IsActive = true;

        var popup = this.ParentOfType<System.Windows.Controls.Primitives.Popup>();
        if (popup != null)
        {
            popup.IsOpen = false;
        }
    }

    private void OnClear(object sender, RoutedEventArgs e)
    {
        if (column.DataControl.FilterDescriptors.Contains(compositeFilter))
        {
            column.DataControl.FilterDescriptors.Remove(compositeFilter);
        }

        Aargang = 0;

        IsActive = false;

        var popup = this.ParentOfType<System.Windows.Controls.Primitives.Popup>();
        if (popup != null)
        {
            popup.IsOpen = false;
        }
    }

}