The labels of the Pie are clipped not only because they are too long but also because the width/height of the Chart is too small. I can suggest you increase the width/height of the chart, so that labels fit in. For the time being I have logged your idea in our feedback portal here
, so that you can monitor, comment or raise its priority by voting on it. I have also updated you Telerik points for sharing your feedback with us.
All the best,
the Telerik team
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