ask the GA creator.

Yes.

I have one of the games from a bundle that has been put up for a giveaway, can I still enter it?

• Only with the express permission of the person doing the giveaway, as it is so wasteful to have the duplicate simply disappear into the aether. If the giveaway description says you can, you can, but otherwise assume no and if you are feeling bold, ask the giveaway creator to mention their feelings in that regard in the description section.

Reminds me of a question I've always wondered... How do you check if someone owns DLC or not? The site doesn't seem to prevent me from entering for DLC I already own, and also by default lets me enter for GotY-style games even if I own that release myself.

If the creator doesn't specify his/her intention I usually enter but with the thank you message I add a note that if for him/her is not ok, he can reroll. (he can reroll anyway, but I prefer to tell him anyway)