Texas residents can now sue Facebook, Twitter, and YouTube for allegedly censoring their content, after a federal appeals court sided with the state’s law limiting how social media platforms can moderate their platforms on Wednesday.

The 15-word ruling allowing the law, which was blocked last year, to go into effect has serious implications. Most immediately, it introduces new legal risks for the tech behemoths, exposing them to a potential wave of litigation that legal experts predict will be costly and difficult to defend.

According to Texas law, any social media platform with 50 million or more US monthly users is prohibited from “blocking, banning, removing, de-platforming, demonetizing, de-boosting, restricting, denying equal access or visibility to, or otherwise discriminating against expression.”

According to legal experts, the law creates enormous uncertainty about how social media will actually function in Texas, and raises questions about what users’ online spaces may look like and what content they may find there, if the companies can even run their services at all.

The decision also sets the stage for a Supreme Court showdown over First Amendment rights and, possibly, a dramatic reinterpretation of those rights affecting not just the tech industry but all Americans — as well as decades of established precedent.

In short, the decision has allowed Texas to declare open season on tech platforms, with far-reaching consequences for the rest of the country. It has the potential to reshape all websites’ rights and obligations, our relationship with technology and the internet, and even our basic, fundamental understanding of the First Amendment.

But that all changed this week, when a three-judge panel at the Fifth Circuit Court of Appeals confused social media platforms with internet service providers, questioned whether Facebook and Twitter are websites, and expressed surprise that a service like Twitter could “just decide” what content appears on its platform as a matter of course.

We are now in uncharted territory. For as long as the major social networks in the United States have existed, they have been able to rely on Section 230 of the Communications Decency Act, which provides a liability shield for how platforms handle user-generated content. Section 230 has saved many tech platforms from lawsuits over the years. However, a new Texas law is about to change everything. The opponents of the tech industry have never faced legislation like HB 20.

One option for tech platforms is to completely disable all algorithmic content filtering and ranking. While it’s tempting to imagine all social media looking like the clean, reverse-chronological feed you can find on Twitter today (if you know where to look), Daphne Keller, a platform liability expert at Stanford University, says that’s only the best-case scenario and not the most likely.

After all, removing algorithmic amplification of some content could be interpreted as a form of demotion, which is prohibited under HB 20, according to Kosseff. “Who knows!” he exclaimed, emphasizing how vast the possibilities are.

In the face of all this uncertainty, tech platforms may simply give up and cease offering services in Texas entirely. However, even leaving Texas may not be enough to save them. A prohibition on discriminating against Texans based on their geographic location is buried in the law. By leaving Texas, tech companies risk being accused of geographical discrimination against Texans in violation of House Bill 20.

Following Wednesday’s decision, the HB 20 case could end up before the Supreme Court. The groups that challenged HB 20 have at least two obvious options: they can directly appeal to the Supreme Court, or they can request a rehearing before a larger panel of appellate judges in the hopes of a different outcome — which could eventually lead to a Supreme Court appeal anyway.