X has sent cease-and-desist letters to Nitter, the open-source project that lets users view X posts without an account, demanding a permanent takedown. The project’s flagship instance, nitter.net, is now offline, and its creator, known as Zedeus, is seeking legal advice. X accuses Nitter of unlawfully circumventing its API and accessing data and session tokens. This follows X’s earlier technical efforts to block Nitter in 2024. Other Nitter instances have also received similar letters. The move reflects a broader industry trend of social networks restricting third-party readers. For X users who relied on Nitter for ad-free, account-free browsing, this marks the end of an era.