This paper questions state sovereignty at borders, by referencing the contradictions that a border control approach based upon security concerns creates, and the distortions between societies of norms and situations of exception that the European migration and asylum policies generate. Meanwhile sovereignty should correspond in a legal theory perspective to authority, its expressions in the European borders consist essentially in domination. By investigating the hiatus between how sovereignty ought to be in theory and how it is observed in practice, sovereignty appears to be diffracted n the thickness of the frontiers. Are explored the methods states develop directly or indirectly inside the border zones, exploiting the concept of heterotopia Michel Foucault forged : such tool underscores how states construct and exploit frontiers as useful margins and dissolution zones. Three methods – extraction, classification, obliteration – are highlighted that correspond to the main purposes of border surveillance – control, select, remove -.