The below is an excerpt from SAC058: "SSAC Report on Domain Name Registration Data Validation" https://www.icann.org/en/system/files/files/sac-058-en.pdf The excerpt is about contact data specifically. As I mentioned on the RDS mailing list last week, WHOIS conveys kinds of registration data other than contact data. These include whether a domain is registered, creation and expiration dates, the name and ID of the sponsoring registrar, what nameservers are delegated to the domain, and so on. We (and users) should absolutely expect an RDS to provide accurate data in those areas. Those kinds of data are not subject to the vagaries that contact data is. For example, a registry is required to accurately timestamp a domain creation, and the RDS should provide the same timestamp. If a domain is in the registry, the RDS should not return a "domain does not exist" response (outside any update-time SLAs). For the kinds of data mentioned in the paragraph above, providing data that is accurate is an RDS's very reason for being. SAC058 is worth the time to read, and I recommend it to all members of the WG. It provides a useful framework for talking about contact accuracy and validation, and it poses questions and makes formal recommendations directly to our WG. <snip from SAC058> 2.1 Why Accurate Registration Data is Important In SAC003: WHOIS Recommendation of the Security and Stability Advisory Committee, the SSAC outlined two principal reasons to maintain accurate registration data: technical and legal. The technical rationale is that if there are problems with or abuse originating from a resource (e.g., a domain name, route, or Internet Protocol (IP) address), the registration data for the resource is the only source for finding the contact information of the responsible party. For some legal and other law-related purposes (e.g. serving court papers), the registration data may be the only source for finding the contact information for the responsible party. In SAC 010: Renewal Considerations for Domain Name Registrants, the SSAC observed that registration data often contain "stale" contact information and that this problem can cause difficulties when registrants seek to renew a domain name or modify DNS information. Stale information may prevent registrars from notifying a registrant that a domain registration is about to expire or that changes, possibly unauthorized, have been made to his domain registration. Failure to update information may result in domain hijacking or a dispute over the "ownership" of a domain. It is important to note in understanding the scale of potential problems from inaccurate information that the difficulties do not arise only in criminal matters. The contexts also can include a simple contact issue, as described above with regard to domain renewals, civil and administrative law enforcement, private actions, and public needs to contact registrants that might arise, for example, when a consumer wants to reach an online seller. </snip> All best, --Greg