If you run a location that's part of a franchise, multi-location business, or corporate group, Square can share a wide range of your data — including your customers' transaction records and your employees' information — with the top-level account holder of that group. This applies even though the trigger is described as 'elected' or 'notified,' meaning you may not get a real opportunity to say no. This is a brand-new category of third party that did not exist in the prior notice.
“we may share your Square Account Data, Usage Data and Commercial Information (including customer directory data, customer transaction data and employee/staff data) with the account holder of that merchant group”
What you can do — If you operate within a franchise or multi-location merchant group, review the Square for Multi-Legal Entities Terms of Service and check your account settings to understand what data is shared with your group's account holder.