Gridsum Holding Inc. announced that it has cooperated with the Mobile Marketing Association China ("MMA China") on a General Invalid Traffic ("GIVT") List program to launch a Distributed Invalid Traffic Filter System (the "DIF System"). Invalid traffic is a substantial problem for marketers. The cutting edge of GIVT consists of traffic identified through routine means of filtration executed through application of machine intelligence, lists and other standardized parameter checks. In practice, GIVT traffic is identified via pattern recognition leveraging available lists of IP addresses, IMEI numbers, browser identifiers and other signatures, or from activity clearly matching non-human patterns of behavior, such as a click frequency.