An undertaking is any entity engaged in an economic activity, regardless of its legal status or the way it is financed. 

The concept of the undertaking can encompass multiple separate legal entities where those separate entities together form a single economic unit. The single economic unit comprises a unitary organization of personal, tangible and intangible elements which pursues a specific economic aim on a long-term basis.  The concept of the undertaking or single economic unit allows parent companies to be held liable for the anti-competitive behavior of their subsidiaries but also ensures that intra-group agreements fall outside the scope of the Article 101(1) prohibition because such agreements do not involve two distinct undertakings.

An individual is also capable of constituting an undertaking for the purposes of competition law.