Consent, the final frontier. International commercial arbitration is a dispute resolution mechanism embedded in consent of the parties involved. Presentation of such a mutual understanding is done through an arbitration agreement. However, the aim of this paper is to analyse whether its contractual, indeed consensual, nature is the only element which the courts use to identify the subjects who may compel or must be compelled to arbitrate disputes, or whether they employ other considerations as well. The paper will focus on extension doctrines which might be less known even to a professional audience: piercing of the corporate veil, estoppel & group of companies. A review of selected case law leads to a conclusion that consent-finding analysis is definitely a starting point of any analysis. However, at the same time courts and arbitrators do indeed use tools of contract interpretation and the ones based on equity or good faith considerations to establish, and exceptionally force, the implication of consent far beyond what is obvious.