After I filed my trademark application, will the trademark examiner look for unregistered trademarks to decide whether my mark is trademarkable?
And the answer to that is no. All they care about are trademarks that were registered or applied for through their Trademarks Office to decide whether there's a likelihood of confusion.
That means two things. First of all, if you do a proper trademark search, you will have a pretty good idea as to whether your trademark is registrable or not. And notice that I said, "proper trademark search". It doesn't mean that all you do is just look for the identical trademark in the automated database. You want to make sure that the search is done by somebody who understands what they're doing and that they look at not only identical trademarks but also similar trademarks.
The other thing that it means is that after the trademarks examiner approves your trademark, there's still a risk that somebody with an unregistered trademark can oppose your trademark and claim their prior right. The Trademarks Office is not going to know about this, they won't care about this, they won't give you any heads-up even if they google and find the same brand actively used by somebody else. But you should have common sense in deciding whether or not you want to file for a trademark that's identical to a trademark that someone has been using for many years without getting it registered.
Whether or not they're going to oppose is a different issue. Your registration, especially in Canada and the U.S., won't allow you to stop that other company from using their trademark that they had been using prior to your application.
So do your research, don't file for a trademark that you know is confusingly similar to somebody else's identical trademark, but the short answer to this question is, no, the trademark examiner is not going to look anywhere outside of the Trademarks register to see if your mark is confusingly similar for the purposes of approving your application for publication.
Disclaimer: Please note that this post and this video are not and are not intended as legal advice. Your situation may be different from the facts assumed in this post or video. Your reading this post or watching this video does not create a lawyer-client relationship between you and Trademark Factory International Inc., and you should not rely on this post or this video as the only source of information to make important decisions about your intellectual property.