In comments submitted to the All Party Parliamentary Internet Group, which is investigating digital rights management (DRM) technologies, the British Library has expressed strong concerns about the long-term viability of electronic resources. Content producers increasingly use DRM to limit unauthorized access to electronic materials, but officials from the library said the protections also threaten legitimate uses of content. Use of materials held by libraries constitutes an important exception to copyright laws, according to Clive Field, the British Library's director of scholarships and collections, but DRM tools inadvertently upset the balance between appropriate exceptions and the rights of content owners. Moreover, long-term access is at risk. Even when copyright expires for a work, the DRM tools applied to its electronic version will still be in place. If the owner cannot be contacted, there might be no way to unlock materials that are no longer covered by copyright. "This will fundamentally threaten the longstanding and accepted concepts of fair dealing and library privilege," according to the British Library's statement, "and undermine...legitimate public good access."