I'm a canadian citizen. I lived and worked in USA for 12-13 years under a VISA (Not a US citizen and not a permanent resident). I've been back to Canada since 2011. I do not own anything in USA. Since in Canada I've been working for a Canadian Company.
When I opened my investment account (2011) they asked me if I had US issued social security number. I said yes, so they asked me to fill in a W9. Was that the right thing to do?
Since I lived and worked legally in USA, I was issued a SSN and I still have the number.
As Heath pointed out bellow I should not have signed a W-9 From. The canadian bank I use, had told me fill in the wrong form. The people that work there do not know the difference between having a SSN and being a US person. After a month of going back and forth, today they told me that I had to fill in a W-8BEN which would apply from 2015 forward, for 2011-2014 they can't do anything...