151That argument must be rejected. Indeed, it is clear from the case-law that Article 65(1) CS prohibits agreements which ‘tend’ to prevent, restrict or distort normal competition. It follows that that provision prohibits agreements the purpose of which is to restrict competition but the anti-competitive effects of which have not been established. Since the Commission found, in recital 399 of the first decision, that the agreement had been designed to fix prices on the basis of which the restriction or control of production and/or sales was also agreed, it was not obliged to demonstrate that there had been an adverse effect on competition in order to establish an infringement of Article 65(1) CS (Case C-198/99 PEnsidesa v Commission [2003] ECR I-11111, paragraphs 59 and 60, and Case T-141/94Thyssen Stahl v Commission [1999] ECR II-347, paragraph 277) (see also recital 463 of the first decision). In any event, contrary to the applicant’s claim, the Commission did examine, in the interests of completeness, the effects of the agreement and concluded, on the basis of the facts and matters set out in recitals 513 to 524 of the first decision, that the agreement had had actual effects. In order to dispute that conclusion, in Case T‑472/09, the applicant merely argues, in the context of the present plea, that purchasers of reinforcing bars, in particular the national association of iron millers (‘Ansfer’), never learned of, or suspected the cartel. The fact that purchasers of reinforcing bars were unaware of the cartel cannot, however, prove that the agreement had no effects on the market, as the applicant alleges.