Please examine the following help article on the matter: http://www.telerik.com/help/aspnet-ajax/radsocialshare-appearance-controlling-dialog-position.html
. Put shortly - you can use the RadCompactButton's DialogLeft and DialogTop properties to control the position of the compact popup on the screen. You could set them to the absolute position on the viewport you wish the popup to appear. Currently there is no way to make the popup relative the RadSocialShare itself.
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