A facility or infrastructure which is necessary for reaching customers and/or enabling competitors to carry on their business. A facility is essential if its duplication is impossible or extremely difficult due to physical, geographical, legal or economic constraints. Take, for example, a national electricity power grid used by various electricity producers to reach the final consumers: since it would not be viable for these producers to build their own distribution network, they depend on access to the existing infrastructure. Denying access to an essential facility may be considered an abuse of a dominant position by the entity controlling it, in particular where it prevents competition in a downstream market.

Source: Glossary of terms used in EU competition policy, Antitrust and control of concentrations, European Commission, 2002