Intertrust said an agreement by British mobile carrier Vodafone this week to license its anti-piracy software would be a breakthrough deal to protect online music.

Anti-piracy technology for digital media, also known as Digital Rights Management (DRM), controls usage of digital music, video and other content to prevent illegal copying and file-swapping.

DRM technology is already used in online stores such as iTunes from Apple and Connect from Sony, but there is not yet an open standard that would allow consumers to buy a song in one vendor's store and forward or copy it to a device from another vendor.

With this deal, Vodafone gains access to the Intertrust's entire portfolio of patents, which it will need to use either of the two open standards that are being developed for anti-piracy software.

Intertrust's technology is going into the open standards being set by the Open Mobile Alliance of electronics companies and operators as well as those from the Marlin alliance of the world's top four consumer electronics companies.

The Marlin standard has been agreed and will be available next year.

Sony and Panasonic, Samsung Philips have said they will introduce electronics devices in 2006 based on Marlin software.

These firms are already able to build digital rights management systems, because they own important chunks of the underlying technology themselves.

But the patent holders for the Open Mobile Alliance's anti-piracy technology -- including Sony, Philips, Intertrust and ContentGuard -- have not agreed on the terms for licensing it.

The group proposed a reduced tariff in April of $0.65 per mobile phone and an annual $0.25 per service per subscriber, but operators and handset makers find that too expensive, pointing out that the joint license payments would exceed the total revenues from digital entertainment at the moment.