Jeremy Stoppelman. REUTERS/Jim Young In 2013, the FTC declared that Google was not an illegal monopoly. But the decision hasn't stopped Yelp CEO Jeremy Stoppelman — one of Google's most outspoken competitors — from telling stories about the company.

In a podcast interview with Re/Code's Kara Swisher, Stoppelman claimed that Google was engaged in "a lot of cloak and dagger stuff" around its lobbying efforts in Washington.

He pointed to one example: Google was found to have donated $760,000 to the George Mason University Law and Economics Center, which later published a number of favorable research papers that argued that Google hadn't violated any laws.

"I think Google has become extremely savvy about lobbying," Stoppelman said, crediting Google's former CEO turned executive chairman. "Eric Schmidt was on the opposite side of this conversation back when Microsoft was on top. He's the expert. He learned the playbook. He was in my chair essentially a couple of decades ago."

Stoppelman was referring to when Microsoft was declared a monopoly by the DOJ in 2000. At the time Schmidt was running Novell, a competitor to Microsoft, and it never recovered from Microsoft's assault.

As for Google, Stoppelman thinks the company's tactics have gotten nastier as mobile eats the tech world.

"Google has completely lost its mind," Stoppelman said. "They're like, 'Local [content] is really important. We don't like this trend toward apps, so we're going to do whatever the hell we want to try and preserve our monopoly and our dominance.' They would love for us to live in a world where web was still central and the most relevant."

Stoppelman delved into Yelp's history with Google. In 2009, Google tried to buy Yelp for a reported $550 million-plus, but Yelp walked away. Stoppelman described that to Swisher as "some drama in 2009."

Eric Schmidt. via Reuters Later, Google licensed Yelp's reviews for its Maps product, but Yelp ended that agreement after "their page started looking more and more like a Yelp page" and after Google started adding its own reviews to Maps.

"The final insult was they no longer had our licensed content, so then they decided: 'We're just going to steal their content,'" he accuses.

By "steal" Stoppelman meant that Google crawled Yelp to index it for Google's search engine — which Yelp gives it permission to do for search — and Yelp reviews wound up used in other ways, he believes.

"The reality is there are lots of people who feel very strongly [about Google] the way that I do. But very few have been able to step out of the shadows and talk about this," he says.

Stoppelman thinks that Google might be taken to task by the European Union, which announced an investigation into Google in April.

"The conversation happening in the EU is interesting. I feel some momentum there. I think they are asking the right questions," Stoppelman said. "I'm optimistic we'll have a better outcome there."

He thinks the FTC could still change its mind about Google. The FTC was reportedly looking at Google again in terms of its control of Android.

The irony is that Yelp itself has also faced down its accusers via the FTC.

In April 2014, the FTC had received more than 2,000 complaints about Yelp from 2008 through March 2014, The Wall Street Journal reported. People were complaining about its advertising-sales practices and how it deals with negative reviews. For instance, one business owner who was battling it out with Yelp over negative reviews later discovered that her company's name changed on Yelp to something offensive.

In January, the FTC closed the investigation, taking no action against Yelp. That was the second time the FTC investigated Yelp's advertising practices and took no action against Stoppelman's company.