Customer search to find parents lacking Shipto State

I would really appreciate help with this saved search. We are heavy users of Individual- and Company-type customers, with much focus on individuals because they read/consume our subscriptions.

Many of the company records do not have addresses, but the subcustomers have addresses. With a saved search, I'm trying to identify these customers, but two factors are stopping me:

1. Parent Customer Fields > Shipping State does not exist on Criteria tab (nor does Shipping State exist from the general list of fields on Criteria tab)

2. I can't figure out how to write the formula to access the Parent's {shipstate}. None of these is working: {parent.shipstate}, {parentid.shipstate}, {parent_id.shipstate}, {childof.shipstate}, {child_of.shipstate}