The paper analyses to what extent the owners of smart speakers, such as Amazon Echo and Google Home, can be considered joint controllers, and what are the implications of the household exemption under the GDPR, with regard to the personal data of guests or other individuals temporarily present in their houses. Based on the relevant interpretations of the elements constituting control and joint control, as given by the Art. 29 Working Party and by the European Court of Justice (in particular in the landmark cases Wirtschaftsakademie, Jehovah’s Witness, Ryneš, and Fashion ID), this paper shows how the definition of joint control could be potentially stretched to the point of including the owners of smart speakers. The purpose of the paper is, however, to show how the preferred interpretation should be the one exempting owners of smart speakers from becoming liable under the GDPR (with certain exceptions), in the light of the asymmetry of positions between individuals and companies such as Google or Amazon and of the rationales and purposes of the GDPR. In doing so, this paper unveils a difficult balancing exercise between the rights of one individual (the data subject) and those of another individuals (the owner of a smart speaker used for private and household purposes only).