Ownership inside the billing system
Who owns invoice data? What billing systems' terms say
Updated
Most invoicing systems leave the invoices with the business that issued them; the clause to watch is the one that lets the vendor keep an anonymised or aggregated copy.
The invoices stay the business's
Invoice Ninja says the user account owns all data generated in it, Invoice Simple that customer content is owned by the customer, and Esker's TermSync terms that you own all rights in your data and the documents carrying it. 11 of the 21 systems on our board say so; the rest are silent in the document we read.
The anonymised copy the vendor keeps
Invoice2go says it owns all aggregate or anonymous data and may disclose it for marketing and reporting, and Tipalti that it may disclose aggregated or anonymised customer data for its own purposes, including data products for third parties. Invoice Ninja is the exception that says it will not access or distribute account data.
Before you talk to a buyer
List each system the invoices passed through, note its anonymised-use clause, and describe the archive in the enquiry form.