The European Commission has reportedly expanded its informal antitrust investigation concerning the two new-generation digital video disk (DVD) formats that compete against each other. The commission recently enquired a number of studios asking to explain the reasons to back one or another format.

“We have sent a request for information to a number of studios concerning possible discrimination against one or other DVD format,” the Commission spokesman Jonathan Todd said on Tuesday, reports Reuters news-agency.

In late July, 2007, the European Commission initiated investigation concerning the battle between Blu-ray and HD DVD formats that fight to become the replacement for contemporary DVD format. The Commission demanded to find out whether the licensing terms of the Blu-ray or HD DVD formats could break European Union competition rules, however no formal investigation was started. The current enquiry is also a part of informal investigation.

“We’re at the stage of basic fact-finding. We have not opened a formal investigation,” Mr. Todd confirmed.

The enquiry to movie studios may place them into a tough situation. On the one hand, they are asked about possible restrictive agreements between them and either Sony-led Blu-ray association or Toshiba-driven HD DVD promo group.

Blu-ray and HD DVD formats compete for replacing the DVD standard. HD DVD discs can store up to 15GB on a single layer and up to 30GB on two layers. Its competitor, Blu-ray, can store up to 27GB per single layer and up to 50GB on two layers, but Blu-ray discs are more expensive to produce.

The HD DVD is pushed aggressively by Toshiba, NEC, Intel and Microsoft as well as being standardized at the DVD Forum, which represents over 230 consumer electronics, information technology, and content companies worldwide. Blu-ray is backed by Sony and Panasonic, which are among the world’s largest makers of electronics. Among Hollywood studios HD DVD is supported by Warner Bros. Studios, New Line Cinema, Paramount Pictures and Universal Pictures, whereas Sony Pictures, Walt Disney, Warner Bros. and Twentieth Century Fox endorse Blu-ray.