Steam family share playing together

If my friend would share to my account and to HIS alt account at the same time and he plays from his alt where I play from my main account, can we play at the same time over a Steam account?

1 Answer

No. Only one person can use a given shared library at a time. If it's shared with multiple people, only one of them may use it at a time.

See Steam Support:

Can two users share a library and both play at the same time?

No, a shared library may only be played by one user at a time including the owner and even if they want to play different games.

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