Blizzard on Stream Sniping.

We’ve continued to see reports regarding someone live streaming their match, and their opponent watching the stream in order to gain an in-game advantage (also known as stream sniping). While this is obviously poor sportsmanship on the part of the one viewing the stream, we’d like to clarify that this is not a violation of any current policies. In fact, we cannot enforce any ‘fair play’ policies if a user chooses to provide their opponent an advantage. If someone in-game chooses to tell their opponent every move they’re making, thereby informing them how to counter it, we cannot conclude that any violation has taken place. Even if this could be considered a violation, we simply cannot micro-manage every streamed match to ensure the opponent was not looking at it, or using it to their advantage. It goes far beyond the scope of what we’re able to enforce. It’s advisable for those streaming to take precautions, including delaying their streams by a significant amount of time, to avoid any potential advantage they may be providing their opponent.

We are absolutely able to enforce, and will continue to do so, violations that include harassment of others in-game, use of hacks, abuse of our reporting tools, and attempts to disrupt the gameplay of others. If you believe that someone is in violation of the game rules it does not warrant behavior, language, or abuse that would earn you, yourself, a suspension from the game. If you'd like to report an offense, please report the player using clear and descriptive language only once; support will review that report and take action based on the validity of the complaint, not the persistence of the reporting.

The intent with our policies is to ensure a fair and fun experience in Blizzard games, but the act of providing a window into your game for your opponent to see is not considered a violation, should they choose to use that to their advantage. We encourage anyone streaming to keep this in mind while doing so.