Understanding the technology behind online advertising is critical to navigate the significant privacy and other legal issues in play. The risks associated with getting it wrong are sizeable. For example, following nine years of litigation, Google Inc. has agreed to pay a $22.5 million settlement to a proposed class of advertisers who claimed Google had placed their ads on inactive websites. At a recent PLI program, Jonathan Mayer, Stanford University attorney and computer scientist, explained the technology behind tracking, targeting and ad delivery, as well as the “high-frequency trading for eyeballs” ad bidding exchange process. See also “Keeping Up With Technology and Regulatory Changes in Online Advertising to Mitigate Risks” (Jan. 6, 2016).