PC giant Valve has said that developers and publishers cannot promote non-Steam editions of their games on its storefront.
That's going by an updated FAQ about community hubs on the platform's dev portal, Steamworks, in which Valve says that companies can only talk about the Steam version of their games.
"In the game you ship via Steam, and in communications on Steam, you may only promote the Steam version and its availability via Steam, and not other distribution outlets," the updated FAQ said.
"This applies both to full versions of your game and to content patches that change the existing version."
This is likely due to the increased competition in the PC games store space, not least from Fortnite maker Epic. The firm has shaken this off and spoken about the virtues of having more players in the sector, but it's likely wary of losing its position as the top dog PC games store.