On 14 September 2010, Advocate General Mazak (AG) gave an opinion on an appeal by General Quimica (GQ), Repsol Quimica and Repsol YPF concerning the attribution of parent company liability for its subsidiary’s participation in a price-fixing rubber chemical cartel (T-85/06). The appellants argued that the General Court incorrectly rejected evidence put forward to rebut the presumption that the parent companies had decisive influence over GQ’s conduct. There is a general presumption that a parent company with 100 per cent control over a subsidiary is in a position to exercise decisive influence over that subsidiary’s conduct. However, that presumption may be rebutted on a case-by-case basis. The General Court should have examined the evidence, rather than simply relying on the presumption. The AG therefore advised the ECJ to set aside the General Court’s findings on this point. However, the actual evidence submitted by the appellants in this instance was not, according to the AG, sufficient to rebut the presumption of decisive influence. The AG further concluded that the presumption of decisive influence would apply to the ultimate parent company where there is a chain of ownership (e.g. where the parent company owns 100 per cent of a subsidiary, which in turn owns 100 per cent of shares in the subsidiary committing the infringement).