It's search and ads, which may or may not be their "core" as they've got a number of other properties (mail, tumblr, flickr, media). Not to mention that their entire shareprice is basically propped up by the value of their Alibaba investment.
I was under the impression their other properties are included (mail, tumblr, flickr), and only patents and Alibaba holdings are excluded -- is that not the case?