According to the Wall Street Journal, in 2010, a fresh batch of ad-tech upstarts dared to threaten Google's empire. YouTube's CEO Neal Mohan, who once helmed Google's display-ads division, penned a note suggesting they "pick up the one with the most traction and park it somewhere." And park it they did—Google snapped up AdMeld for a cool $400 million in 2011, only to shut it down two years later after siphoning off its tech for their ad exchange, AdX.

The Justice Department claims this was part of Google's grand strategy: buy out budding rivals, corner the market, and lock customers into their ecosystem by making them pay for one tool to access another.

In a 2016 email, Google exec Jonathan Bellack pondered the ethics of owning the platform, the exchange, and a massive network, likening it to Goldman or Citibank owning the NYSE.

Fast-forward to 2018, and another Google exec, Chris LaSala, lamented the "irrationally high rent" Google was extracting from AdX users, noting that AdX wasn't adding any real value but merely running the auction.

Former exec Eisar Lipkovitz testified that Google's dominance in ad tech led to conflicts of interest, and his attempts to lower AdX's cut were rebuffed.

The Justice Department wrapped up its case with testimonies from Google customers, including Stephanie Layser from News Corp, who felt she had no choice but to use Google's tech to avoid losing millions in ad revenue.

In her opening statement, Google's lawyer, Karen Dunn, argued that no one can predict where the industry will be in five years.

As the Wall Street Journal succinctly put it, Google contends that focusing on display ads is passé as the industry shifts to apps, social media, and streaming services. Far from monopolising, Google is losing ground.