OpenAlex is a promising open source of scholarly metadata, and competitor to established proprietary sources, such as the Web of Science and Scopus. As OpenAlex provides its data freely and openly, it permits researchers to perform bibliometric studies that can be reproduced in the community without licensing barriers. However, as OpenAlex is a rapidly evolving source and the data contained within is expanding and also quickly changing, the question naturally arises as to the trustworthiness of its data. In this report, we will study the reference coverage and selected metadata within each database and compare them with each other to help address this open question in bibliometrics. In our large-scale study, we demonstrate that, when restricted to a cleaned dataset of 16.8 million recent publications shared by all three databases, OpenAlex has average source reference numbers and internal coverage rates comparable to both Web of Science and Scopus. We further analyse the metadata in OpenAlex, the Web of Science and Scopus by journal, finding a similarity in the distribution of source reference counts in the Web of Science and Scopus as compared to OpenAlex. We also demonstrate that the comparison of other core metadata covered by OpenAlex shows mixed results when broken down by journal, where OpenAlex captures more ORCID identifiers, fewer abstracts and a similar number of Open Access status indicators per article when compared to both the Web of Science and Scopus.

As Open access (OA) is often perceived as the end goal of scholarly publishing, much research has focused on flipping subscription journals to an OA model. Focusing on what can happen after the presumed finish line, this study identifies journals that have converted from OA to a subscription model, and places these “reverse flips” within the greater context of scholarly publishing. In particular, we examine specific journal descriptors, such as access mode, publisher, subject area, society affiliation, article volume, and citation metrics, to deepen our understanding of reverse flips. Our results show that at least 152 actively publishing journals have reverse-flipped since 2005, suggesting that this phenomenon does not constitute merely a few marginal outliers, but instead a common pattern within scholarly publishing. Notably, we found that 62% of reverse flips (N = 95) had not been born-OA journals, but had been founded as subscription journals, and hence have experienced a three-stage transformation from closed to open to closed. We argue that reverse flips present a unique perspective on OA, and that further research would greatly benefit from enhanced data and tools for identifying such cases.

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.

The assignment of document and publication types in scholarly databases plays an important role in bibliometrics, for example in decision-making or university rankings. However, scholarly databases apply different curation strategies and taxonomies when classifying documents, which makes it difficult to compare results from different database providers. In this study, the academic literature databases OpenAlex, Web of Science, Scopus, PubMed, and Semantic Scholar are used to analyze the extent of data variation and compare different approaches to taxonomy and data curation. Using a shared corpus of 9,575,603 publications from 2012 to 2022, we found large differences in the classification of document types such as research articles and editorials in these databases. We also found that many records without a publication type in OpenAlex are classified as conference proceedings in both Scopus and Semantic Scholar.

With the growth of open access (OA), the financial flows in scholarly journal publishing have become increasingly complex, but comprehensive data on and transparency of these flows are still lacking. The opacity is especially concerning for hybrid OA, where subscription‐based journals publish individual articles as OA if an optional fee is paid. This study addresses the lack of transparency by leveraging Elsevier article metadata and provides the first publisher‐level study of hybrid OA uptake and invoicing. Our results show that Elsevier's hybrid OA uptake has grown steadily but slowly from 2015 to 2019, doubling the number of hybrid OA articles published per year and increasing the share of OA articles in Elsevier's hybrid journals from 2.6 to 3.7% of all articles. Further, we find that most hybrid OA articles were invoiced directly to authors, followed by articles invoiced through agreements with research funders, institutions, or consortia, with only a few funding bodies driving hybrid OA uptake. As such, our findings point to the role of publishing agreements and OA policies in hybrid OA publishing. Our results further demonstrate the value of publisher‐provided metadata to improve the transparency in scholarly publishing.

The ongoing controversy surrounding transformative agreements, which aim to transition subscription-based journal publishing to full open access, highlights the need for large-scale studies assessing the impact of these agreements on hybrid open access. By combining multiple open data sources, including cOAlition S Journal Checker, Crossref, and OpenAlex, we present a novel approach that analyzes over 700 agreements. Results suggest a strong growth in open access, from 4.3% in 2018 to 15% in 2022. Over 5 years, 11,189 hybrid journals provided open access to 742,369 out of 8,146,958 articles (9.1%). Authors who could make use of transformative agreements contributed 328,957 open access articles (44%) during this period, reaching a peak in 2022 with 143,615 out of 249,511 open access articles (58%). While this trend was predominantly driven by the three commercial publishers Elsevier, Springer Nature, and Wiley, open access uptake varied substantially across journals, publishers, disciplines, and countries. In particular, the OECD and BRICS areas revealed different publication trends. In conclusion, this study suggests that current levels of implementation of transformative agreements are insufficient to bring about a large-scale transition to full open access.