The NeoGAF forums, a constant source of rumors and speculation, have given birth to a suspicion that Valve is planning to integrate a form of digital game lending into its popular Steam client. User Grief.exe has pulled a set of prompts from the latest Steam Beta update that deal with the service’s English UI.
These lines refer to a “Shared game library” and include messages to both a “Owner” and a “Borrower” regarding games being already in use or presently unavailable.
If this is real, it appears that the owner of a game will be able to designate friends as “borrowers,” who will be able to play games the “owner” possesses as long as the owner themselves is not playing. Should the owner want to play, it appears that the borrower will be informed that it is “time to quit.” If the borrower tries to play a game that is already in use, Steam will inform them that it is unavailable.
This model puts most of the power into the hands of the owner, who seems to have permanent priority of games that they have bought themselves, and doesn’t serve as a way to play multiplayer together off of one copy of the game. Could this also be a preview of how the Xbox One’s family sharing will function?
Source: NeoGAF