You can't sue someone for promising something wasn't officially signed by both parties. It's quite easy actually. Also, since you never had to fill in your name, social security number, official address etc, how would you prove it was you? This means all you can bring to court is saying you participated in a technically voluntary promotional stunt, for which no official reward was determined, by a company that has zero obligation to fill your needs, and you didn't get the rewards you hoped for. Best case scenario is that you sue them for discrimination because you're the only one not getting paid, yet discrimination is insanely hard to prove. You'd spend thousands on legal fees, not to mention the lawyers salary (+- 100$ an hour), and you'd most likely not even make a dent. 99/100 it doesn't even reach a judge. What I suggest you do is be patient, remove your claims, and talk to them via skype about the situation when they announce the bounty distribution is completely over.