@Walmart is creating the Walmart Exchange (WMX), a digital targeting, buying and optimization platform. WMX will give vendors tools they can utilize with Walmart that will make their digital marketing more effective, allow vendors to see how their marketing is affecting Walmart, as well as speed up reporting. Moreover, Walmart plans to buy media on behalf of their suppliers. Walmart might be doing this to lower supply chain costs and supplier ad budgets to translate into lower prices for Walmart. - Link