Advocates for the digital rights of consumers have expressed concerns over a proposed class action settlement involving CDs released by Sony BMG.

The class action settlement between Sony BMG and Canadian customers who bought CDs that included a hidden copy-protection program goes to court for approval next week.

The Electronic Frontier Foundation, a U.S. digital rights advocacy group, says the proposed settlement does not include provisions included in the U.S. class action settlement, including the requirement to disclose any future use of digital rights management and to provide a program that uninstalls such a system.

The proposed settlement for Canadians — $7.50 plus tax for each customer — is also about 10 per cent lower than the American settlement.

Legal scholar Michael Geist posted on his blog a copy of an affidavit from the company's vice-president of legal affairs, Christine Prudham, which he called "the only key settlement document that Sony has not provided to the public."

"The affidavit seeks to explain why Sony BMG Canada believes it is appropriate to grant Canadian consumers fewer rights than their U.S. counterparts," wrote Geist on his blog. 

"The heart of the argument revolves around a series of copyright-related arguments that are utterly without merit," he wrote.

Geist could not be reached for comment.

Blog revealed details of scheme

The affidavit in question, Exhibit C, now appears on Sony BMG's webpage about the case.

Details of the rootkit copy protection scheme were revealed on a programmer's blog in October 2005.

Mark Russinovich found an unexplained process running on his Windows computer after he played a recently purchased Sony BMG CD.

The copy protection software, called Extended Copy Protection or XCP, is installed when the CD is put into a computer. The program uses a technique called a rootkit to hide the fact that it is running, making it more difficult to disable.

Security experts say the fact that the Sony program was hidden wasn't itself harmful.

However, the program remains active on the computer even when the CD isn't being played and at least one computer virus has been written to hide behind the same cloak.

Two days after it was discovered, Sony released a free update to its software that "removes the cloaking technology component," but not the copy protection.

Prominent suppliers of anti-virus programs, including Computer Associates and Microsoft, included XCP in their definitions for malicious software.