Mozilla faces massive revenue hit if DOJ wins Google Search monopoly case

The long-running antitrust battle between the US Department of Justice and Google just sent a potentially massive shockwave toward an unexpected target: the Firefox browser. Testimony from a Mozilla executive last Friday painted a grim picture, suggesting the browser’s very existence could be threatened if the DOJ gets its way regarding Google’s search deals.

Mozilla CFO Eric Muhlheim called the situation “very frightening” while testifying in court, according to reporting by The Verge. The core issue revolves around the DOJ’s push to stop Google from paying companies like Mozilla to make Google the default search engine in their browsers. The court has already determined Google holds an illegal monopoly in search, partly due to these exact kinds of deals.

For Mozilla, the non-profit behind Firefox, this isn’t just a minor inconvenience. Muhlheim revealed that Firefox accounts for about 90 percent of Mozilla’s revenue. And a staggering 85 percent of that comes directly from Google. Losing that income stream almost overnight could force “significant cuts across the company,” potentially triggering a “downward spiral,” Muhlheim warned. If Firefox development suffers, users might leave, further reducing revenue and leading to more cuts. He bluntly stated this could “put Firefox out of business.”

It feels like a classic case of unintended consequences. The DOJ wants to foster competition, but a key remedy could eliminate one of Google Chrome’s few remaining independent competitors. I remember highlighting how this case could spell disaster for Mozilla last year, but hearing the stark financial numbers laid out in court really drives the point home. Firefox relies on the Gecko engine, one of only three major browser engines globally, and the only significant one not controlled by Big Tech like Google (Chromium) or Apple (WebKit).

Switching search providers isn’t a simple fix either. Muhlheim noted talks with Microsoft about Bing, but expressed concern that without Google bidding, any deal would be far less valuable. Worse, internal Mozilla studies found Bing simply doesn’t generate as much revenue from user searches compared to Google. They even tried making Yahoo the default years ago (2014-2017), an experiment that ended badly as users disliked the experience and switched browsers.

While the DOJ hopes its broader remedies might eventually create more viable search competitors, Muhlheim argued Mozilla might not survive the wait. “We would be really struggling to stay alive,” he testified. It leaves Mozilla in a deeply uncomfortable position, financially dependent on the very monopoly the government is trying to dismantle. The final court ruling on remedies is still pending, but for Firefox users and fans of a more diverse web, the future looks worryingly uncertain.