The most important information which is necessary in order to complete the Reputation Check form is the IP addresses and domain names from which email messages are sent. This information can be obtained from your IT department. The Reputation Check form also requests information about the monthly volume of email messages sent and the number of email addresses on your mailing list. In addition, the Reputation Check form asks whether messages are sent from an IP address used solely by your organization or if messages are sent from a shared IP address, for example, by an email service provider.