How does Google know the originating country?

I have a new .com client who's business is in Canada. His site is hosted in the US. His registry information is hidden. His website features an international blend of content, however it's predominantly US-centric content.

The one clue Google has is that the nameservers are .ca.

His site ranks well on google.ca but poorly on google.com.

My questions are:

1. How does Google determine where the site owner is, or do they at all?

2. If it's determined the owner is in a different country than the US, will Google automagically rank him below US-based competitors?

I am probally way of base here but Is it possible to use a phone number?

I found networks of sites owned by the same person googled the phone number to find them (I know interlinking between the sites is the way this is normally found) but do you think google might use email and phone numbers to see this?

and then maybe use phone numbers for other reasons, just thinking about a far fetched though here.

Why would google care where the site owner is? Google uses IPs, set geo region in webmaster tools, country tld,s and geo links to determine geo relivance (possibly/probably user behavior also).

That just makes no sense.. Why would google care where the owner lives? How does this have any relevance to the quality of their SERP results.

I have no idea why they'd care or if they care, however in this case it seems they may. The .ca SERPs are good, but the .com SERPs are lack-luster. Could be purely coincidental. The user behavior idea is a thought though, he does receive a good share of his traffic from Canada, however #1 rankings in .ca are probably the factor there...

Just wondering if anyone has experienced anything like this... regardless we're going to switch to US .com based DNS. If anyone cares, I'll let you know the affect it has on the SERPs.

One of the major GEO locations serps factor are getting links from targeted country.

I have a client based in Canada with similar details. He ranked very well in google.ca and not so good in google.com (US results)

We have added a bunch of US links over the last 3-4 months and he now ranks well in both.

In the beginning he had more US links than he did Canadian links so I was unsure as to whether links would fix the problem. I couldn't figure out why he ranked so well in Canada with only a small percentage of links coming from that country.

Having seen the results of adding the links I am pretty sure that it was due to the fact that .ca serps were far less competitive.