Nintendo is taking another stab at using YouTube's Content ID system to claim part of the advertising revenue of "let's play" videos that feature its games: http://www.wired.com/2015/03/nintendo-youtube-creators/. Where do content creators stand when it comes to Canadian copyright law and claims by video game companies?
For Canadian content creators there are three key legal sources:
1. The YouTube Terms of Service.
2. The Copyright Act.
3. Important copyright case law such as CCH Canadian Ltd. v. Law Society of Upper Canada and Entertainment Software Association v. Society of Composers, Authors and Music Publishers of Canada (part of what's been dubbed the "copyright pentalogy").
The specific parts of the Copyright Act that are of interest to creators are the provisions that set out what counts as "Fair Dealing": ss. 29, 29.1 and 29.2. There is also an exception for non-commercial user-generated content: s. 29.21.
It's important to understand that copyright law divides game rights into (at least) two buckets: music and graphics. Although the graphics are likely owned by one entity, different pieces of music may have different owners (and there may be a question as to whom the correct owner is). A YouTube video will also likely feature the trademarks of the video game company (trademarks are a different but related area of law).
If you're wondering how copyright or trademark law applies to your specific situation then you should contact a lawyer. Alternatively you can also do your own research at a law library for free (but please understand that this is a complex area where even a lawyer might not be able to give you a clear answer).
The Great Library in Toronto is operated by the Law Society of Upper Canada but it's open to non-lawyers and is a great place to find textbooks about copyright law. Case law can be researched using the free CanLII search engine.
If you are a content creator considering challenging a claim made through Content ID you should also consider the practical consequences of using YouTube's appeal system: you may end up with a "copyright strike". Also, you will be providing information to someone who might file a lawsuit against you for copyright infringement (although this is not common practice in Canada).
One potential response: some creators have already decided to stop producing videos that feature Nintendo games. That's probably not the response that Nintendo was hoping for.