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Stability: in the event of a Registrar business or technical failure, it could be beneficial to ICANN and registrants to have the full set of domain registration contact data stored by four organizations (the Registry, the Registry's escrow agent, the Registrar, and the Registrar's escrow agent), which would be the case in a ‘thick’ registry.
Data escrow: ‘thick’ Whois might obviate the need for the registrar escrow program and attendant expenses to ICANN and registrars.
Mailing list archives: http://forum.icann.org/lists/gnso-stability-thickwhois/
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