This chapter explores the regulatory challenges posed by the ‘extreme public sphere’: Alt Tech platforms that serve as media infrastructures for far-right ideologies. Triggered by the deplatforming of extremist accounts from mainstream platforms, platforms such as Gab, Bitchute, and Rumble emphasise near-absolute freedom of expression and minimal content moderation. These platforms amplify toxicity and potentially radicalise users through echo chambers. The chapter critiques the European Union’s regulatory responses, including the Digital Services Act and Codes of Conduct/Practice on hate speech and disinformation. These instruments assume that platforms are economically motivated, incentivised to maintain ‘clean’ environments for advertisers and users. However, Alt Tech platforms primarily act politically and rely on donations and subscriptions rather than advertising. As they have fewer users than mainstream platforms, they evade the risk audits and stringent obligations mandated for Very Large Online Platforms. Despite nominal compliance with legal requirements, such as user-driven moderation, Alt Tech platforms continue to host significant volumes of hate speech and disinformation. While regulation is essential, addressing the broader societal conditions that enable far-right ideologies – structural discrimination, inequality, and distrust – is critical. A whole-society approach that considers the entire communicative ecosystem could foster a more inclusive and resilient digital public sphere.