Thank you for contacting us.
Indeed, the PivotGrid.dll is referencing the TelerikData.dll because of the export functionality. Generally, you don't need the TelerikData assemblies in scenarios where assemblies are dynamically loaded as it will only be loaded by the runtime when you try to export the data from RadPivotGrid. However, in scenarios where assemblies are statically resolved (ILMerge or WiX for example), not including the assembly causes errors.
Currently, we don't have any plans on removing this reference but we will surely consider this in the future. I have logged this in our feedback portal and you can track the progress here: http://feedback.telerik.com/Project/154/Feedback/Details/126334-fix-radpivotgrid-has-a-dependency-on-telerikdata-dll-and-chartview-dll-which-mak
I have updated your Telerik points for bringing this to our attention. For the time being, you can safely include the TelerikData assembly in your merged one. This should only result in an increase of a few KBs of the total size of the merged assembly.
If you have any other questions, I will be glad to assist you.
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