268In that regard, in the first place, it should be noted that the system of penalties for infringement of the competition rules, as established by Regulation No 1/2003 and interpreted by the case-law, shows that, by reason of their very nature, cartels merit the most severe fines. The actual impact which they may have had on the market, particularly the question of the extent to which the restriction of competition resulted in a market price higher than that which would have obtained in the absence of the cartel, is not a decisive factor for determining the level of fines (see, to that effect, Musique Diffusion française and Others v Commission, paragraph 233 above, paragraphs 120 and 129, and Case C-286/98 PStora Kopparbergs Bergslags v Commission [2000] ECR I-9925, paragraphs 68 to 77; see also the Opinion of Advocate General Mischo in Case C-283/98 PMo och Domsjö v Commission [2000] ECR I-9855, I-9858, points 95 to 101).