The owner of a project called our company & they are asking for our Hiring Customers Invoices, because we sent them a second month notice. Are we permitted to send it? I only ask, because I don't know if our hiring customer is marking up our prices to them, and our invoices would let them know what we charged our hiring customer, and do not want to cause problems with them. I have never had a owner call for our hiring customer's invoice, so I wanted to verify what I needed to do.