A lawsuit filed Wednesday against Meta argues that US law requires the company to let people use unofficial add-ons to gain more control over their social feeds.

It’s the latest in a series of disputes in which the company has tussled with researchers and developers over tools that give users extra privacy options or that collect research data. It could clear the way for researchers to release add-ons that aid research into how the algorithms on social platforms affect their users, and it could give people more control over the algorithms that shape their lives.

The suit was filed by the Knight First Amendment Institute at Columbia University on behalf of researcher Ethan Zuckerman, an associate professor at the University of Massachusetts—Amherst. It attempts to take a federal law that has generally shielded social networks and use it as a tool forcing transparency.

Section 230 of the Communications Decency Act is best known for allowing social media companies to evade legal liability for content on their platforms. Zuckerman’s suit argues that one of its subsections gives users the right to control how they access the internet, and the tools they use to do so.

“Section 230 (c) (2) (b) is quite explicit about libraries, parents, and others having the ability to control obscene or other unwanted content on the internet,” says Zuckerman. “I actually think that anticipates having control over a social network like Facebook, having this ability to sort of say, ‘We want to be able to opt out of the algorithm.’”

Zuckerman’s suit is aimed at preventing Facebook from blocking a new browser extension for Facebook that he is working on called Unfollow Everything 2.0. It would allow users to easily “unfollow” friends, groups, and pages on the service, meaning that updates from them no longer appear in the user’s newsfeed.

Zuckerman says that this would provide users the power to tune or effectively disable Facebook’s engagement-driven feed. Users can technically do this without the tool, but only by unfollowing each friend, group, and page individually.

There’s good reason to think Meta might make changes to Facebook to block Zuckerman’s tool after it is released. He says he won’t launch it without a ruling on his suit. In 2020, the company argued that the browser Friendly, which had let users search and reorder their Facebook news feeds as well as block ads and trackers, violated its terms of service and the Computer Fraud and Abuse Act. In 2021, Meta permanently banned Louis Barclay, a British developer who had created a tool called Unfollow Everything, which Zuckerman’s add-on is named after.

“I still remember the feeling of unfollowing everything for the first time. It was near-miraculous. I had lost nothing, since I could still see my favorite friends and groups by going to them directly,” Barclay wrote for Slate at the time. “But I had gained a staggering amount of control. I was no longer tempted to scroll down an infinite feed of content. The time I spent on Facebook decreased dramatically.”