The viewing key is configurable and does not necessarily reveal all the transaction details. There are a three options. If address viewing is enabled, a viewing key holder can follow assets from the original creator to all subsequent recipients. If amount viewing is enabled, a viewing key holder can see the volume of the asset being transferred at the level of individual transactions, but cannot see recipients. If both are enabled, a viewing key holder can see the complete transaction graph for the asset. Another attribute that can be revealed is the hiding factor of the record commitment. This is important for freezing policies described below.