[Solved]-Highcharts renderer.text as export only-Highcharts

You are right - there you should use load event to add extra text for exported image: http://jsfiddle.net/3bQne/88/

chart.exportChart(null, {
        chart: {
            backgroundColor: '#FFFFFF',
            width: 972,
            height: 480,
            events: {
                load: function () {
                    this.renderer.text('Filtered', 5, 10)
                        .attr({
                        rotation: 0
                    })
                        .css({
                        color: '#4572A7',
                        fontSize: '8px',
                        fontStyle: 'italic'
                    })
                        .add();
                }
            }
        }
    });