How can I tell if a key were redeemed or not ?

Be careful with comments like that, even joke begging/asking for keys can get you suspended.

That was too quick

You can't do that officially, but if you give it to a group of friends & people you trust, they'll likely accept your request to delete the giveaway.

If you don't deliver your key or delete a giveaway you would lose a slot i guess. I don't know if you get suspended or not.

True. :/

yes, they can make it, and welcome to the key generators world
no thx, its good as it is

Like Jastrzap mentioned, that would be pretty much welcoming keygens with open arms.
At the very least, the "key checker" would have to be extremely limited. (10 keys checking an hour perhaps?)

Valve don't want people to trade keys.They specifically ban users from trying to trade them on their official forums. Keys are designed to redeem physical copies and are intended to be purchased from official retailers and then redeemed by said purchaser.

I think Valve will never do that. And I don't think it is due to security reasons. The reason is very simple - money. All keys come from outside the steam store, So why Valve would help his competition? It doesn't make any sense for them, as this would be very helpful for trading, which is bad for Steam store and whole the gifts idea. I think this is the main reason, not the key generators.

It doesn't. Duplicate keys still result in "Product already owned" instead of "Duplicate product".

Sorry I misunderstood you. Before the current system they had you connect your steam account and if you clicked you would reddem the key directly to your account. And before that you had the button that hide the keys. But sometimes I had the same game 2 or 3 times by buying it in different bundles. And sometimes I tried to redeem the same game 2 times or more, by mistake (don´t remembering I already had the game or just putting the key without even looking which game I was redeeming). So after a bunch of this small mistakes, I started writing the keys in an excel sheet and marking the redeemed ones. Now I found the sheet and don´t know about the status of some unmarked keys.

That's what ALWAYS happens, even with used keys

Nice. I didn't thought of that. Thank you, they are just a handful of keys, I will ask them :D.

Why dont you contact on steam, email or in winners own created GA instead of bumping a 4 year old thread?

And besides, winner has 7 days to mark as received.

And if they don't, after 7 days ask support to do it - the game is in their account.

This comment of yours could quality both as "unreasonable bumping" and "calling out", either of which is a site rule violation.
Put another way, please leave matters related to specific users off of the forums whenever possible, and please don't resurrect old threads unless there's a decidedly constructive benefit to the action.

If they don't have a previous giveaway that you can contact them through, and you can't get a hold of them through Steam or e-mail, and you're dead-set on trying to contact them, then the only real remaning option is to put in a support ticket and ask staff to give them a poke. Otherwise, just wait the seven days and put in either a Request Received Feedback [if they've revealed the key] or Request New Winner ticket [if they haven't]. In the case of Request Received Feedback, if the key has been revealed and the game is in their account, then you don't even need to wait 7 days- just put the ticket in as soon as you're aware of the situation, and let staff sort it out.

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