The European Patent Office (EPO) will not be issuing patents for stem cells that have been obtained through the destruction of human embryos. The ruling announced last November invokes so-called 'morality clauses', invalidating the University of Wisconsin-Madison's key patent for a method of obtaining embryonic stem cell cultures from primates, including humans (the Wisconsin Alumni Research Foundation/Thomson patent will still be upheld in the US). Although the European ruling expressly rejects destruction of the human embryo, there is still some confusion. Aurora Plomer, professor of law and bioethics, University of Sheffield, says the ruling has “left open the question of whether specific moral exclusion extends to downstream derivative products, that is, products based on stem cell lines whose original derivation would have involved destruction of a human embryo.” In Europe the situation remains quite fluid, with researchers bypassing the EPO by filing applications directly to their national patent office. But the stem cell ruling may have further implications, such as “increased costs for the industry, as investors revert to discrete selective national filings to secure patent protection on [human embryonic stem cell] inventions in favorable environments,” says Plomer. This ruling comes as experts warn that the UK may lose its place as leader in the field, as Obama's administration has pledged to inject more money into federal funding of stem cell work.