As part of its mounting U.S. rollout of content-enhanced and copy-protected CDs, Sony BMG Music Entertainment is testing technology solutions that bar consumers from making additional copies of burned CD-R discs. Since March the company has released at least 10 commercial titles -- more than 1 million discs in total -- featuring technology from U.K. anti-piracy specialist First4Internet that allows consumers to make limited copies of protected discs, but blocks users from making copies of the copies.