A former Google executive told colleagues around 2008 and 2009 that the goal was to “crush” rival advertising networks, according to evidence prosecutors presented at its antitrust trial on Wednesday.

“We’ll be able to crush the other networks and that’s our goal,” David Rosenblatt, said Google’s former president of display advertising of the company’s strategy, reported Reuters, citing notes shown in court.

The statement was highlighted to support the U.S. Department of Justice’s claim that Google tried to dominate the market for ad exchanges that sit between both sides — buy and sell —in the advertising market.

But it’s not just that one statement. A company’s culture creates a monopoly, whether unintentional and unknown or intentional and known, through a series of actions. Proving a monopoly requires prosecutors to string together a series of evidence.

However, a lawyer told MediaPost that Google did not need to have intent to become a monopoly — it just happened through the series of actions such as acquisitions and building platforms that allowed them to own the technology.

Rosenblatt joined DoubleClick in 1997, and served as its CEO from 2004 to 2008. In 2007, Google bought DoubleClick for $3.1 billion. Rosenblatt then served as Google’s president of global display advertising until 2009.

Rosenblatt’s comments were included in a series of emails initialed by former Google ad executive Brad Bender, who spent more than 10 years at DoubleClick and joined Google as part of the acquisition in 2008.

Bender told the court he had forwarded Rosenblatt’s notes to his team at the time, describing them as worthwhile to read.

The Monopoly Report pointed to the discussion about header bidding in the email as “pretty damning.”

The email from Bender to the display team outlined former DoubleClick CEO Rosenblatt’s overview of Google’s display strategy.

One of the most interesting comments in the email centered on a reference to the sustainability and value of the exchange business.

Rosenblatt wrote that “nothing really matters but the platform. Nothing has such high switching costs. If there’s a better network or exchange, you can just switch to it. Switching platforms is a nightmare. Takes an act of God to do it.”

The email provides this example (I have summarized the content. You can read it here.): Let’s say DoubleClick and Google Ad Manager serve 18 billion impressions per day. And then, once we have a much more competitive GCN and a viable exchange, we’re able to peel off even 10% of that inventory to monetize somehow. And I think the number should be higher. So that’s 1.8 billion impressions daily. If we monetize that at a dollar CPM and multiply that by 365 days, you see how valuable the platform is.

A former Google exec told colleagues the goal was to “crush” rival ad networks. That was only one email. Here’s what others explained, according to evidence prosecutors presented at the company’s antitrust trial Wednesday.