Patent regimes have gone through important changes in the past two decades, most of them in the direction of ‘strengthening patent rights’, in the sense of reinforcing the exclusive rights conferred to patent holders and expanding their coverage. OECD countries have experienced an upward harmonisation of their patent regimes based on the view that easily enforceable patents and broader rights for patent holders are beneficial for innovation. Reforms have been mainly led by requirements set out in international treaties, and decisions taken at major patent offices and courts. This paper compares and reviews the main changes to patenting regimes in Europe, Japan and the United States and ...