Can a website see that a user is from Google SSL?

Question

Google wrote:

However, for organic search results on SSL search, a web site will only know that the user came from google.com.

http://googlewebmastercentral.blogspot.com/2011/10/accessing-search-query-data-for-your.html

How is this possible when Referer == NULL?

Answer 1

When you search you're doing the query over HTTPS. When you click the link, that is an HTTP click, and the referer comes from google.com.