In one of the first Article 82 cases, Hoffmann-La Roche, the European Court of Justice gave the definition of market dominance, which is still used nowadays: “[the dominant position] relates to a position of economic strength enjoyed by an undertaking, which enables it to prevent effective competition being maintained on the relevant market by affording it the power to behave to an appreciable extent independently of its competitors, its customers and ultimately of the consumers. Such a position does not preclude some competition, which it does where there is a monopoly or quasi-monopoly, but enables the undertaking, which profits by it, if not to determine, at least to have an appreciable influence on the conditions under which that competition will develop, and in any case to act largely in disregard of it so long as such conduct does not operate to its detriment”.
The Hoffmann-La Roche delineated also the concept of abuse of a dominant position, as a behaviour “which, through recourse to methods different from those which condition normal competition in products or services on the basis of the transactions of commercial operators, has the effect of hindering the maintenance of the degree of competition still existing in the market or the growth of that competition”.
Abusive behaviour consists mainly of exclusionary practices as predatory pricing, exclusive dealing, refusal to supply, and tying.
It is worthy to emphasize that European law does not punish the dominant position in itself, just its abuse. However, in the practice of European law, a dominant firm might not be allowed to engage in the same practices as non-dominant firms.