Google (Temporarily) Blocks AppNexus From Its Ad Exchange

There was a big shakeup in the online advertising world last weekend: Google cut off AppNexus from its ad exchange, forcing the startup to direct its clients to purchase ad inventory directly from Google. The move comes only a few weeks after AppNexus raised a huge $50 million round, which included a big chunk from Microsoft. And the timing couldn't be worse for AppNexus — because of the huge surge in shopping, last week was among the busiest, if not the busiest, time of the year for these platforms. AppNexus offers, among other things, a real-time platform for purchasing ad inventory from ad exchanges — the largest of which is Google's. One industry expert I spoke with guessed that Google's exchange could account for 50% or more of AppNexus inventory, so this is a very big deal for the company and its clients.