As Sir Richard Arnold capably explains elsewhere in this volume,2 when legislative changes are made to intellectual property laws, provision needs to be made for mediating discontinuities between the old and new regime. In the United Kingdom, this is typically done by so-called “transitional provisions,” which specify the extent to which the old law is maintained in relation to existing rights, interests and relationships, or how far (and from when) the new law becomes applicable. In intellectual property statutes, these typically provide that rights in existence before the change continue to subsist, and that rightholders benefit from expansion of rights but may be subject to broadened or altered exceptions and limitations. In EU law, general principles operate to produce similar effects (without the specific intervention of the legislator),3 though these are sometimes made explicit in EU IP legislation.4