"Mass-copying has gotten to such a level that we had better take a stand to protect the artists

Adam White, Universal Music

The record label is also being extremely cautious about where promotional copies of the album's first single, Without Me, are going, fearing leaks on to the internet will affect sales.

If Universal go ahead with the plan, it would mark the company's biggest attempt to protect its artists from piracy.

There has been a strong push from the major labels towards copy-proof material but until now it has tended to be on a limited basis.

Sales slump

Albums from Celine Dion, *N Sync and Natalie Imbruglia have all had technology added to prevent them being copied.

The widespread leak on to the internet of the Oasis comeback album Heathen Chemistry will further add fuel to the industry's concerns about piracy.

Eminem's third album is due for release on 3 June, so any decision on copyright protection will need to be taken swiftly.

Piracy has recently been blamed for a 5% drop in the world's music sales.

The music industry took quick action to try and halt the illegal downloading of music from the internet which can easily be copied on to CDs.

Consumer complaints

Sites such as Napster were shut down by legal wrangles because unlicensed music was being swapped on its service.

But some consumers have complained that albums with anti-piracy equipment attached have hindered their ability to play them on their computers or in-car stereos.

Because it has not been used on such an eagerly awaited album before, it has been difficult to gauge reaction.

"Clearly, we will have a better sense of how the market feels about copy-protection when a release of Eminem's stature, should we decide to do it, comes with copy-protection on it," said Universal Music spokesman Adam White.

"Mass-copying has gotten to such a level that we had better take a stand to protect the artists," he added.