Open Data, Open Source and Open Standards in chemistry: The Blue Obelisk five years on

This contribution looks back on the work carried out by the Blue Obelisk in the past 5 years and surveys progress and remaining challenges in the areas of Open Data, Open Standards, and Open Source in chemistry.We show that the Blue Obelisk has been very successful in bringing together researchers and developers with common interests in ODOSOS, leading to development of many useful resources freely available to the chemistry community.The Blue Obelisk movement was established in 2005 at the 229th National Meeting of the American Chemistry Society as a response to the lack of Open Data, Open Standards and Open Source (ODOSOS) in chemistry. While other scientific disciplines such as physics, biology and astronomy (to name a few) were embracing new ways of doing science and reaping the benefits of community efforts, there was little if any innovation in the field of chemistry and scientific progress was actively hampered by the lack of access to data and tools. Since 2005 it has become evident that a good amount of development in open chemical information is driven by the demands of neighbouring scientific fields. In many areas in biology, for example, the importance of small molecules and their interactions and reactions in biological systems has been realised. In fact, one of the first free and open databases and ontologies of small molecules was created as a resource about chemical structure and nomenclature by biologists [1].The formation of the Blue Obelisk group is somewhat unusual in that it is not a funded network, nor does it follow the industry consortium model. Rather it is a grassroots organisation, catalysed by an initial core of interested scientists, but with membership open to all who share one or more of the goals of the group:？ Open Data in Chemistry. One can obtain all scientific data in the public domain when wanted and reuse it for whatever purpose.？ Open Standards in Chemistry. One can find visible community mechanisms for protocols and communicat