It looks as though Twitch's subscriber exclusive streams could have repercussions for a few developers.

Twitch rolled out Subscriber streams last week - a new feature that allows broadcasters to host private streams just for their subs. However, some users are aware that the feature is actually against some developer's terms of service.

Reddit user justalazygamer noticed clauses in the terms of service for a number of developers including Blizzard, Riot Games, Valve and CD Projekt Red. All of the clauses state that creators cannot put their games behind a paywall.

Blizzard's limitation of usage says "neither you nor the operator of any website where your Production(s) may be viewed can force a viewer to pay a "fee" to be able to view your Production(s).", while Valve's TOS says "you can't charge users to view or access your videos". 

These terms mean that streamers may not be able to play games from these companies in Twitch's subscriber-only mode. This rules out many popular titles on Twitch including Overwatch and Hearthstone, League of Legends, Dota 2 and Counter-Strike: Global Offensive. 

There are also questions surrounding Twitch's subscriber-only mode itself. Private streams are a good way to reward paying fans but can impact discoverability, and they're only viable to streamers that already have large paying fanbases. This restriction on some of the platform's most-watched titles could make the mode even more situational.