This study investigates the development of open access (OA) to journal articles from authors affiliated with German universities and non-university research institutions in the period 2010–2018. Beyond determining the overall share of openly available articles, a systematic classification of distinct categories of OA publishing allowed us to identify different patterns of adoption of OA. Taking into account the particularities of the German research landscape, variations in terms of productivity, OA uptake and approaches to OA are examined at the meso-level and possible explanations are discussed. The development of the OA uptake is analysed for the different research sectors in Germany (universities, non-university research institutes of the Helmholtz Association, Fraunhofer Society, Max Planck Society, Leibniz Association, and government research agencies). Combining several data sources (incl. Web of Science, Unpaywall, an authority file of standardised German affiliation information, the ISSN-Gold-OA 3.0 list, and OpenDOAR), the study confirms the growth of the OA share mirroring the international trend reported in related studies. We found that 45% of all considered articles during the observed period were openly available at the time of analysis. Our findings show that subject-specific repositories are the most prevalent type of OA. However, the percentages for publication in fully OA journals and OA via institutional repositories show similarly steep increases. Enabling data-driven decision-making regarding the implementation of OA in Germany at the institutional level, the results of this study furthermore can serve as a baseline to assess the impact recent transformative agreements with major publishers will likely have on scholarly communication.

In the current scientific and political discourse surrounding the transformation of the scientific publication system, significant attention is focused on Diamond Open Access (OA). Diamond OA is characterized by no charges for readers or authors and relies on monetary allowances and voluntary work. This article explores the potential and challenges of Diamond OA journals, using Germany as a case study. Two key questions are addressed: first, the current role of such journals in the scientific publication system is determined through bibliometric analysis across various disciplines. Second, an investigation is conducted to assess the sustainability of Diamond OA journals and identify associated structural problems or potential breaking points. This investigation includes an in-depth expert interview study involving 20 editors of Diamond OA journals. The empirical results are presented using a landscape map that considers two dimensions: 'monetized and gift-based completion of tasks' and 'journal team size.' The bibliometric analysis reveals a substantial number of Diamond OA journals in the social sciences and humanities, but limited adoption in other fields. The model proves effective for small to mid-sized journals, but not for larger ones. Additionally, it was found that 23 Diamond OA journals have recently discontinued their operations. The expert interviews demonstrate the diversity within the landscape and the usefulness of the two dimensions in understanding key differences. Journals in two of the four quadrants of the map exemplify sustainable conditions, while the other two quadrants raise concerns about long-term stability. These concerns include limited funding leading to a lack of division of labor and an excessive burden on highly committed members. Gift-like contributions, while appealing, also present challenges as potential donors not only decide whether to contribute but also how to contribute, potentially creating friction between the gift and the journal's requirements. Furthermore, journals in the lower right quadrant often rely on third-party funding, necessitating a transformation once the funding expires. Common pathways for sustaining operations include lobbying for funding at the journal's home institution or increasing reliance on gift-based completion of tasks. These findings underscore the need for the development of more sustainable funding models to ensure the success of Diamond OA journals.

Academic data infrastructures facilitate bibliometric research and reporting, as they link bibliometric data with research interests. In Germany, the Kompetenznetzwerk Bibliometrie (KB), a national consortium of 22 institutions, serves this purpose by hosting, probing, and curating large-scale bibliometric raw data from commercial and open providers. Users at partner institutions regularly apply the data infrastructure in workflows. Due to its former focus on commercial data, the KB’s infrastructure has not been detailed transparently to date. However, as an increasing number of bibliometric publications and reports rely upon it, this article provides a comprehensive documentation of the KB’s infrastructure specifically designed for bibliometric applications. It explains the conceptual considerations employed to define the infrastructure’s technical characteristics and procedures. Descriptions are provided regarding (1) the technical infrastructure, (2) the KB’s own database schema consistently applied across several bibliometric databases, (3) processing bibliometric raw data, (4) multi-dimensional quality assurance processes, and (5) additional data curation. By making these procedures transparent and open to scrutiny, we aim to bolster the reliability of our infrastructure and facilitate reproducible research while contributing to the broader discourse on transparency in the field of bibliometrics and providing input to other organisations developing similar infrastructures. Peer Review: https://www.webofscience.com/api/gateway/wos/peer-review/10.1162/qss.a.20

The article analyzes possible financial effects of Gold Open Access based on article processing charges. It responds to the question whether different cost sharing models lead to the same or different financial burdens for research organizations. The distributional effects are calculated for five models. For the overwhelming majority of organizations, all models result in similar expenditures, but there are also organizations where the difference between most and least expensive model results in a considerable amount. Therefore, it is likely that cost sharing models will become an issue in the debate on how to shoulder a transformation toward Open Access.