League of Legends developer Riot has unleashed something of a bombshell on the pro-gaming community of streamers. The company operates a competitive e-sports league, the League of Legends Championship Series (LCS), that's about to start its fourth season. Teams participating in the competition have to agree to a contract, and according to portions of the contract leaked to onGamers, those contracts will ban LCS participants from streaming a range of games that compete with League of Legends.

Strikingly, the contract prohibits not merely streaming these games during or adjacent to LCS events: they're banned entirely. If any competitor in LCS streams one of these games, they (or their team) are in breach of contract.

These prohibited games include direct competitors in the multiplayer online battle arena space such as Dota 2 and Heroes of Newerth, other competitive titles such as the StarCraft franchise, and, peculiarly, the PlayStation 3 title Fat Princess. Additionally, the rules prohibit the streaming of gambling sites, as well as promoting pornography, firearms, and non-over-the-counter drugs.

The terms do have some omissions; they don't include first-person shooters such as Counter-Strike: Global Offensive, which are also played competitively.

League of Legends is currently top dog in the e-sports world, with the most players and some of the largest competitions. Riot has done a lot to promote the game as an e-sport. In addition to organizing LCS, Riot also sponsors the teams that participate in order to help gaming become truly professional, with players depending on it for their income.

Riot's director of e-sports, Whalen "RiotMagus" Rozelle, justified the restrictions on the basis of that support, positioning it as a necessary part of the professionalization of League of Legends. He likened the prohibition to those faced by professional athletes: if Nike sponsors your team, you don't go on camera wearing Reeboks. Rozelle argued that every time an LCS participant streams, they're "the face of competitive League of Legends"—even if they're not playing League of Legends.

But streaming is an increasingly important part of the video gaming community. The PlayStation 4 can stream gameplay to Twitch TV so that gamers can share their experiences live, and the Xbox One will gain this feature in the future. Some of the biggest and most popular broadcasters are professional gamers: the matches they play tend to be high-skill and hence interesting, and they have growing fanbases who want to follow them online.

Online streaming can also provide some amount of additional revenue for the pros: Twitch, for example, supports both advertising and paid monthly subscriptions to individual streamers. With pros streaming to tens of thousands of fans, this is a valuable resource that Riot is undermining.

Unsurprisingly, the decision has been met with dismay by both fans and pro gamers alike. Playing other games on stream (for example, while waiting to find a League of Legends game) is commonplace, with Blizzard's Hearthstone being a noted favorite. It's a move that looks defensive on Riot's part, as if the company were threatened by the growth of, in particular, Dota 2. Many in the community reject Rozelle's argument, saying that the situation is akin to the NBA prohibiting Michael Jordan from playing golf (which it didn't do).