SAN JOSE, Calif. — Apple Inc.'s recent rollout of songs without copy protection software at its iTunes Store has given consumers new flexibility, but questions have emerged over the company's inclusion of personal data in purchased music tracks.

Are the songs that are being billed as free of so-called digital rights management technology really "DRM-free," or are there still strings attached?

The Electronic Frontier Foundation, a consumer watchdog group, said the embedded user information in the purchased track raises privacy issues.

Apple declined to comment.

The trendsetting Cupertino-based company has always embedded user information — a user name and e-mail — into its copy-protected tracks. But until the market-leading iTunes Store began offering DRM-free music last week, no one raised much of a ruckus.

DRM technology puts a sort of software lock on digital songs or movies, dictating where and how the content can be played and distributed. With DRM-free content, some songs purchased from iTunes now work directly on portable players other than Apple's iPod, including Microsoft Corp.'s Zune.

Though piracy of digital music over the Internet remains unabated even with the growth of legitimate online retailers like iTunes, Apple's debut of DRM-free songs could tempt some of its users to share their purchased tracks with others online.

Technology blogs Ars Technica and The Unofficial Apple Weblog were among the first to reveal that personal data remained in the unrestricted iTunes tracks. Their reports last week prompted speculation that the data could be used to trace copies uploaded to online file-sharing networks back to the people who originally purchased the tracks, opening those users to music industry copyright lawsuits.

The Recording Industry Association of America, whose piracy lawsuits have ensnared organized outfits as well as individual grandmothers and youths, declined to comment. EMI Group PLC, the major record label behind Apple's inaugural batch of DRM-free songs, also declined to comment.

The Electronic Frontier Foundation, which also analyzed the DRM-free song files on iTunes, said it did not want to jump to any conclusions on Apple's reasons for embedding the personal data.

Still, the group takes issue with the fact that the personal information stored in this type of song files is not encrypted, said Fred Von Lohmann, an attorney with the San Francisco-based group.

"It's not as bad as leaking your credit card number or your Social Security number, but it's still a pretty careless security leak," von Lohmann said.

Michael Gartenberg, an analyst at JupiterResearch, said he does not think Apple planned to use the personal data as a secretive tracking tool.

"I think it's more of a way of retaining a proof of purchase," he said, adding how the identifying tags on copy-protected tracks likely facilitated Apple's ability to approve user upgrades to previous song purchases.