ELECTRONIC MAIL DELIVERY NEGOTIATION AND REJECTION USING SENDER SPECIFIED ACCEPTANCE CRITERIA VALUES

Processing electronic mail can include receiving, within an electronic mail server, an electronic mail from a sender client system, sending acceptance criteria for a recipient of the electronic mail to the sender client system responsive to receiving the electronic mail, and receiving, within the electronic mail server, acceptance criteria values from the sender client system in response to the acceptance criteria for the recipient. Using a processor of the electronic mail server, a determination is made whether the acceptance criteria values comply with the acceptance criteria. Responsive to determining that the acceptance criteria values are non-compliant with the acceptance criteria, the electronic mail server rejects the electronic mail, wherein the electronic mail is not delivered to the recipient, and providing, to the sender client system, an indication of rejection of the electronic mail including a reason for non-compliance.