AWS Simple Email Service Identity Configuration

I am working on a project to implement an application on AWS that will send customer notifications outbound via the AWS SES service. When setting up the SES identities I have used Domain and Email address identity types to verify the senders. This has worked fine for development where the users are internal.

For a production environment how do I configure SES identities when the outbound emails are from real customers when I do not know or have control of their email domains? I guess some form of anonymous send access would be required.