I have already replied to the support ticket that you have submitted on the same subject.
For convenience I will paste my reply on the forum as well, so the other users who experience similar problem could read it:
Currently we haven't support for auto padding and you set bigger series.padding in order to fit the pie chart with labels inside this box.
In order to implement auto series.padding I would suggest to submit your request in Kendo's UserVoice
so other members of the community can evaluate, comment on and vote for it.
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