Steam Subscriber Agreement wrote:
C. Your Account
You may not reveal, share or otherwise allow others to use your password or Account except as otherwise specifically authorized by Valve.
Your Account, including any information pertaining to it (e.g.: contact information, billing information, Account history and Subscriptions, etc.), is strictly personal. You may therefore not sell or charge others for the right to use your Account, or otherwise transfer your Account, nor may you sell, charge others for the right to use, or transfer any Subscriptions other than if and as expressly permitted by this Agreement (including any Subscription Terms or Rules of Use) or as otherwise specifically permitted by Valve.
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