Following the 1980 US Supreme Court decision to allow a patent on a living organism, debate has continued on the moral issues involved in biotechnology patents of many kinds and remains a contentious issue for those opposed to the use of biotechnology in industry and agriculture. Attitudes to patenting in the life sciences, including those of the research scientists themselves, are analysed. The relevance of morality to patent law is discussed here in an international context with particular reference to the law of the European Patent Convention administered by the European Patent Office (EPO). The EPO has been the principal forum for opposition to such patents and the few cases under dispute in the EPO are reviewed, including patents for the onco-mouse, human relaxin gene, and the PGS herbicidally resistant plant (gmo). Morality provisions in the European Parliament and Council Directive 98/44/EC are also summarised.