Jon von Tetzchner, the founder of both Opera and Vivaldi, believes that Google has gotten too big and "is now in a position where regulation is needed."
In a blog post on Vivaldi's website, von Tetzchner said that his once friendly relationship with Google and its founders has soured across the years.
Von Tetzchner says that after he gave an interview in May this year in which he criticized Google and Facebook for tracking users, Google retaliated two days later by suspending Vivaldi's AdWords account.
The Vivaldi creator says the ban came out of nowhere and the company had received no prior warning about anything that could have led to this radical decision.
When Vivaldi's tech staff reached out to Google, the company had unreasonable demands to have their AdWords account reinstated, such as forcing Vivaldi to list all sorts of links on the Vivaldi download page.
The Vivaldi crew and von Tetzchner were irked by Google's demands, as not even Chrome followed these rules, but also because they felt that Google was abusing its dominant position in online advertising to put Vivaldi in its place after its CEO's comments.
"As the biggest online advertising company in the world, Google is often the first choice for businesses that want to promote their products or services on the Internet," von Tetzchner said. "Being excluded from using Google AdWords could be a major problem, especially for digital companies."
"A monopoly both in search and advertising, Google, unfortunately, shows that they are not able to resist the misuse of power," he continued. "I am saddened by this makeover of a geeky, positive company into the bully they are in 2017."
"I feel blocking competitors on thin reasoning lends credence to claims of their anti-competitive practices," von Tetzchner added, linking to a $2.7 billion fine Google received from the European Union for tinkering with search results to promote its Google Shopping service to the detriment of its direct competitors.
Von Tetzchner's account of dealing with Google is as uncomfortable as the one detailed by ProtonMail's founder in October 2016, when he said Google suppressed ProtonMail from search results for months so it could redirect users to Gmail.
Last week, news also surfaced that Google forced a think tank it was sponsoring to fire an employee that had criticized the company.
The European Commission is currently investigating Google in two other antitrust cases. One is for the Android mobile operating system, where "Google has stifled choice and innovation in a range of mobile apps and services by pursuing an overall strategy on mobile devices to protect and expand its dominant position in general internet search," and the second is for AdSense, where the EU things "Google has reduced choice by preventing third-party websites from sourcing search ads from Google's competitors."
Contacted by Bleeping Computer, Google provided the following statement:
Article updated post-publication to include comment from a Google spokesperson.