As often happens to arguments reaching a peak in interest, platform theory needs to be thoroughly discussed. With the same category indiscriminately applied to Apple and WhatsApp, and to Facebook and Uber, the discourse about platformization has eventually come up against the same problem as outlined in van Dijk’s critique of Castells’ theory on networks, in that it runs the risk of somehow reifying ‘platform’ as a similar universal keyword. In this context, this chapter analyses the most credited hypotheses on platform society from the perspective of critical internet theory, with a specific interest in the mechanisms of economic exploitation of data and user-generated content. To different extents, the three hypotheses show a common underestimation of the role played by human labour, which would require the retrieval of Marx’s labour/value theory.