The recent upheavals in content governance at X and Meta have something in common: both were initiated by the platform's controlling shareholders. As the US economy and government become increasingly dominated by hyperrich tech oligarchs, Elon Musk and Mark Zuckerberg embody a newly assertive ideological force in the governance of the digital public sphere: platform ownership. Yet scholarship on content governance has until now had little to say about ownership or its influence.
To bridge this gap, this article draws on media ownership research and the study of media moguls to ask: who owns the major public communications platforms, and how do these owners influence content governance outcomes? To map platform ownership, I examine public records including SEC disclosures to distinguish individually-controlled oligarchic firms from diversely-held market-controlled firms. On this basis I argue that Meta and X's ownership structure is distinctly oligarchic, as they are more directly controlled by individuals than other major platform firms such as Bytedance, Apple, and Microsoft, and, to a lesser extent, Google, Reddit and Bluesky.
For content governance outcomes, I review evidence of Elon Musk and Mark Zuckerberg controlling content policies at their respective firms, and discuss whether their actions are best explained as ideologically-motivated political instrumentalism, self-interested economic instrumentalism or market-wide commercial logics. I also discuss how ownership influence may be constrained by the professional logics of Trust and Safety management, and point to precedents in media law and policy to constrain owner power and build non-commercial alternatives.