Criminalizing Sex: A Unified Liberal Theory. By Stuart P. Green. [Oxford University Press, 2020. xxvi + 382 pp. Hardback £22.99. ISBN 978-0-197-50748-3.]

scious copying or in determining whether substantial part is taken, is unclear. Goold goes on to discuss the various stages at which the negligence liability should be introduced, such as licensing, infringement, defences, and remedies (pp. 97–105). The difference between introducing negligence liability into the infringement doctrine and the defences is one of burden of proof, and Goold seems to falter on this point. If IP infringement is to remain truly a negligence-based liability, the primary burden of proof to establish negligence must rest on the person claiming negligence, i.e. the IP owner (usually the claimant). On the other hand, if exercising due care (i.e. the lack of negligence) were to be available as a defence, then the burden of proof would rest on the person claiming that due care was exercised, which is the user (normally the defendant). Goold recognises that in ordinary negligence, the reasonable care and therefore, negligence analysis features within the prima facie case being established (p. 99). This appears to suggest that the burden of proof is on the IP owner to prove a prima facie case by showing that the user’s lack of care led to an IP right being infringed. However, he goes on to argue that if the IP owner establishes a prima facie case of infringement (i.e. that the user copied the work or used the patented invention), then a rebuttable presumption in favour of liability would operate, and only if the user introduces evidence that she exercised all reasonable care should the court not hold her liable (p. 100). This appears to suggest that in infringement cases the burden of proof rests entirely on the user to prove that she took all reasonable care, as if it were a defence rather than a component of the tort of infringement itself. A more coherent exposition of the burden of proof would have helped. It appears to make sense to place the burden on the IP owner from an efficiency viewpoint. If the IP owner is the one bearing the burden of proving that reasonable care was not exercised, then the IP owner will be more cautious in ensuring that their valuable creations are registered where possible, and bear the appropriate markings, making their rights discoverable. In summary, however, Goold’s work is a bold effort in addressing an extremely complex area of law, presented in an historical context, enriched by arguments of economic efficiency. Situated at the intersection of IP and private law, Goold’s work is remarkable in demonstrating the role of core doctrines of private law in addressing some of the most pressing issues in IP.