Traded items will be "held" for days unless you have two-factor security.
by Kyle Orland (US) - Dec 10, 2015http://cdn.arstechnica.net/wp-content/uploads/sites/3/2012/10/valve-vulnerable.jpg
Account theft is a common and longstanding problem for all kinds of online gaming services, as I can personally attest after losing all of my Diablo III loot to a hacker a few years ago. But Valve says the problem is reaching epidemic proportions on Steam, with "around 77,000 accounts hijacked and pillaged each month." Since the service launched item-trading features back in 2011, Valve says the problem of account theft "has increased twenty-fold as the number one complaint from our users... What used to be a handful of hackers is now a highly effective, organized network, in the business of stealing and selling items."
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