It is often correctly noted that many datasets got published in the library world with little or no stories about actual use of these datasets. In this talk we want to highlight some of this usage in the context of the hbz linked open data service lobid (which stands for "linking open bibliographic data"). The hbz has been experimenting with linked data technology since 2009. In November 2013 the hbz launched a linked open data API via its service lobid. This API provides access to different kinds of data: • bibliographic data from the hbz union catalogue with 20 million records and 45 million holdings • authority data from the German Integrated Authority File (Gemeinsame Normdatei, GND) with subject headings, persons, corporate bodies, events, places and works • address data on libraries and related institutions, taken from the German ISIL registry and the MARC organization codes data base. The talk starts with a brief outline of the concept and the technology used behind the lobid API and how lobid itself benefits from other linked data sources. After that it is shown how applications are making use of the lobid API, focusing on the development of the North Rhine-Westphalian bibliography (NWBib) as an example. In the end we provide some lessons learned regarding the transformation of legacy data to linked data and the provision of a web API for it. SWIB15 Conference, 23 - 25 November 2015, Hamburg, Germany. http://swib.org/swib15 #swib15