ProtectChartObject Property [Excel 2003 VBA Language Reference]
True if the embedded chart frame cannot be moved, resized, or deleted through the user interface. Read/write Boolean.
Remarks
Setting this property to True will not protect the embedded chart frame from being modified through the object model.
Example
This example protects embedded chart one on worksheet one.
Worksheets(1).ChartObjects(1).ProtectChartObject = True
Applies to | ChartObject Object