Thank you for contacting us.
Currently, it is not supported to perform filtering in the RadGanttView. However, I think that is reasonable request, so I have logged in our Feedback Portal. You can track its progress, subscribe for status changes and add your vote/comment to it on the following link - ADD. RadGanttView - Filtering support for the GanttViewTextViewElement
I have also updated your Telerik points
If you have any additional questions, please let me know.
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