All eyes are on the Hollywood majors this week, after the European Union antitrust commission asked them to explain their policy of releasing on just one of the two competing hi-def disc formats. The regulator has suggested that the policy, most notably used by the Blu-ray camp, might be anticompetitive and in breach of EU antitrust regulations. Fox and Disney are vociferous Blu-ray supporters, while Universal backs only HD DVD. Letters requesting clarification on the policy were sent out in June. As yet none of the studios have replied; they have until Friday to respond. Depending on the quality of the responses, the regulator says it may launch a full investigation.