Four years after Epic sued Google for running an illegal app store monopoly — a case it won this past December — Epic is suing again. The Fortnite game developer has filed a second antitrust lawsuit against Google, and now additionally Samsung, accusing them of illegally conspiring to undermine third-party app stores.

The lawsuit revolves around Samsung’s “Auto Blocker” feature, which now comes turned-on-by-default on new Samsung phones. While it’s turned on, it automatically keeps users from installing apps unless they come from “authorized sources” — namely, Google and Samsung’s app stores. Epic claims there’s no process for any rival store to become “authorized.”

When Epic filed its original lawsuits against Google and Apple in August 2020, it didn’t yet have its own mobile app store. Now, it does: On August 16th, it launched the Epic Games Store on Android globally and on iPhones in the European Union where the EU Digital Markets Act forced Apple to allow alternate stores.

But a month before it could launch its own store, Epic alleges, Samsung suddenly decided to make Auto Blocker more or less on-by-default — making it harder for new phone buyers to install competing apps themselves.

Epic claims it now requires “an exceptionally onerous 21-step process” to download a third-party app store onto a Samsung phone, making it that much more likely users will give up somewhere along the way.

While “21 steps” seems like an exaggeration to me (Epic’s own website claims turning off Auto Blocker takes just four!) I can see the company’s point when I try it on my own Samsung phone. Not only does Auto Blocker prevent me from installing the new Epic Games Store, the “can’t install app” pop-up no longer tells me how to turn Auto Blocker off.

When I search for “turn off auto blocker” in my Samsung phone’s universal search bar, there are no relevant search results; when I search for “auto blocker,” I have to tap through several additional screens to shut it off. One of them asks me if I’m really sure, claiming “Auto Blocker keeps your phone safe by blocking threats and other suspicious activity.”

Today, Epic alleges that promise of safety is entirely bogus: “Auto Blocker conducts no assessment of the safety or security of any specific source or any specific app before blocking an installation,” the legal complaint reads.

“The thing’s not designed to protect against malware, which would be a completely legitimate purpose,” says Epic CEO Tim Sweeney. “The thing’s designed to prevent competition.”

In a roundtable interview with journalists, though, Sweeney admits he doesn’t yet have proof that Google and Samsung colluded — he’s hoping that comes out in the legal discovery process, like so very many embarrassing things did in Epic v. Google. He also admits he didn’t actually ask Samsung if the company would freely make the Epic Games Store an “authorized source.”

Like with Sweeney’s previous lawsuits, he claims that’s because he’s fighting on behalf of all app developers, not just Epic.

“If we’d fought Epic v. Apple and Epic v. Google solely on the basis of Epic getting special privileges, perhaps settlement discussions with Apple and Google might have been fruitful,” says Sweeney. “But if we did that, we’d be selling out all developers.”

Instead, he says, he privately asked Samsung to either change Auto Blocker so it’s turned off by default, or to create “an honest whitelisting process” that would automatically let honest apps through Samsung’s new barrier. When Samsung and Epic couldn’t agree on “the basis” of that whitelisting process, he says Epic threatened legal action, even sharing a draft version of today’s legal complaint with Samsung.

We’ve asked Samsung to confirm or deny whether Auto Blocker actually scans an app for threats or suspicious activity, and whether it worked with Google on the feature. We haven’t heard back yet.

I suspect Samsung will point out that it doesn’t secretly or quietly turn on Auto Blocker, though; it lets users choose. “The default setting for Auto Blocker is set to On in the phone’s initial setup wizard, but you can also change this setting to Off during the initial setup,” the company’s support page notes.

It’s also not yet clear whether Epic has been harmed by Auto Blocker. Only two new Samsung phones have shipped since Samsung turned it on-by-default. While Sweeney claims Google’s previous attempts to add friction to third-party apps (“Unknown Sources”) caused half the people who clicked “download” to give up partway, he admits he doesn’t yet have data showing that the Samsung feature is making things worse.

He says the Epic Games Store has now reached 10 million mobile installs, against a “totally achievable” 100 million target by the end of the year. He characterizes that as “traction but not an enormous amount.”

In Epic v. Google, the company argued that the Unknown Sources install flow made it so hard to attract new users to a rival app store, Sweeney was eventually forced to bring Fortnite to Google’s store even though he promised Samsung he wouldn’t. Though the jury wasn’t asked to decide on “Unknown Sources” specifically, they did decide that Epic was harmed by Google’s behavior overall.

Epic is asking for a jury trial this time as well.

Speaking of Epic v. Google, we’re expecting Judge James Donato to issue his final order there any day now, and it’s easy to imagine a world where Epic v. Samsung gets affected by how he decides to change Google’s behavior. If he grants Epic’s biggest asks, the Google Play Store would be forced to carry the Epic Games Store and other app stores inside of it and third-party app stores like Epic’s would also get access to Google Play’s entire app catalog. In that world, Auto Blocker seems a little less relevant.

But a Google appeal is guaranteed, and Epic is positioning today’s new lawsuit as a way to prevent and dissuade Google and partners from pursuing a “malicious compliance strategy” in the meanwhile. You could even argue that’s what Judge Donato asked for: in Epic v. Google, he repeatedly told Epic’s lawyers that he wouldn’t grant their request for an anti-circumvention provision to keep Google from getting creative with workarounds.

“We don’t do don’t-break-the-law injunctions… if you have a problem, you can come back,” he said last November.

Sweeney wouldn’t necessarily commit to suing other companies that erect barriers to third-party app stores, but says Epic is “watching that very closely.”

“Fortunately nobody has done this but Samsung, and we hope to keep it that way.”