Like all inexpensive ssl certs, the only guarantee of identity is "domain validation" -if you can read mail going to webmaster@, hostmaster@, Postmaster@, or the email address in a Whois lookup for the domain in question, they'll provide you with a signed key for that domain.
There are higher levels of validation - "business validation" usually involves faxing someone copies of various government supplied paperwork and receiving phone calls on publicly available phone numbers (which is just "outsourcing the identity guarantee" to yellow pages or Dun and Bradstreet.) "EV" validation ( for "green address bar as well as padlock icon" security requires all that plus spending lots of money.