This whole industry of game streaming is operating in a gray zone. It's a matter of time before we see some big lawsuits against the streamer and streaming platforms which make a lot of money by publishing the whole content, without any royalties to game developers /publishers. For certain games. it doesn't spoil or ruin the fun factor for viewers, but some others it just removed the incentives to buy a copy of the g…
It's a tough call. Arguably, the player is the performance, against the game as a backdrop. That could be argued as a transformative use. If you make a video of someone playing golf on a Robert Trent Jones golf course, Robert Trent Jones (or his estate) doesn't get royalties. If you make videos of people playing sports with sports gear with prominent logos, that doesn't mean the sports gear company has a copyright interest. You don't have to pay royalties to car companies when their cars appear in a video.
Cut scenes may be an issue, since the player isn't controlling them.
[1] http://www.develop-online.net/analysis/uploading-gameplay-co... [2] http://www.wipo.int/export/sites/www/copyright/en/creative_i...