In his first speech as IAB chairman, Ziff Davis Chief Executive Officer Vivek Shah said members need to take more responsibility for advertising fraud and other tactics that bring down the value of digital products. He said ad buyers, Web publishers and ad exchanges are all culpable. "It seems to me that we have taken a perfect product and by our own actions have made it imperfect. Let's start with traffic fraud. We have reached crisis proportions," Shah said.