Sony BMG Music Entertainment, the world's second largest music label, has become the last of the top four majors to scuttle digital rights management (DRM) software on music downloads.

The other three large record companies including EMI, Warner Music Group and Universal have already begun dropping DRM -- otherwise known as copy protection software.

Sony BMG said it will soon offer gift cards through bricks-and-mortar stores that can be used to redeem music from the Web. After purchasing the cards, called Platinum MusicPass, users scratch the back off to reveal a PIN and then punch that number into Musicpass.com to retrieve full-length albums. Initially, 37 titles will be offered, but only those by the highest selling artists such as Celine Dion, John Mayer, Bob Dylan and Avril Lavigne.

In place of DRM software, the music will be "anonymously watermarked" in an attempt to help the label learn whether songs are being shared on peer-to-peer networks.

Sony ignited a major controversy two years ago when it was discovered that the company had used "rootkit" technology to embed copy protection software in its CDs.

Other efforts to innovate with digital sales by some of the company's competitors include music-loaded USB drives. Warner Music Group, which recently reported that it's the only major record company to grow unit sales in 2007, also released an album by the band Matchbox Twenty on a USB drive fitted into a bracelet.