Party Tax Profiles: Tax Authority - Is it mandatory to setup a Tax authority party tax profile?

Is it mandatory to setup a Tax authority party tax profile? 

The only reason why it might be necessary is if it is used in tax rules, i.e.  I know that E-Bus uses tax registrations in tax determination and tax reporting.  In tax rules we would probably use the tax registration status "Registered" as a determining factor value.   If we enter "REGISTERED" in the Tax registration Status box, then we are required to enter the issuing tax authority, and therefore the Tax authority party tax profile needs to be setup.

Is that correct?

Very much appreciated