They consistently provided grossly inflated (by an order of magnitude) numbers for their user counts and revenue. I honestly would not be surprised if they had lied to 6Waves in order get a merger in the first place.
They were almost banned from Facebook for selling user data to third parties.
Recently, they were contracted to help publish a game developed by an indie. As publishers, they got to see a game that hadn't yet been released. They stalled the indie shop in publishing the game while rushing to create a blatant clone. They then ditched the indie shop and released their own clone.