The following Domain Verification warnings are presented during the OAuth + OpenID authorization process:
When application developers do not verify their website domains with Yahoo!, the user will see the following warning message on the Yahoo! OAuth or OpenID+OAuth Hybrid authorization screen::
"Warning: This website has not been verified by Yahoo!. For your security, we
recommend that you continue only if you trust this website."
While this application may be safe, Yahoo! presents this message to users to inform them about a potentially unsecure application. Yahoo! recommends that all application developers verify their website domains on the Yahoo! Developer Network prior to releasing their applications for the general public consumption.