Massive open online courses (MOOCs) represent a potentially exciting opportunity to use technology to realise many of the long-promised benefits of universal higher education. While there are many positive aspects to the MOOCs on offer and in development, there are also significant ethical concerns arising from various initiatives. These include the academic duties of care and integrity, commercial exploitation of learners, as well as research ethics concerns arising from the analytical and other work being done by academics and institutions. These issues are explored and a set of heuristics for individuals and institutions provided as a starting point for ethical analysis of MOOCs and associated activities.