BASE is a multidisciplinary search engine for scholarly internet resources which have been harvested from several hundred scientific repositories. Some of the indexed resources in BASE are subject to license, while most material is free available ("open access").

The Bibliography of the History of Art (BHA) contains abstracts and indexes of current publications in the history of art, including scholarly journals, conferences, book, exhibition reviews, and exhibition catalogues. The records consist of bibliographic citations, abstracts, and indexing. Note that the database search includes BHA, covering 1990-2007, the International Bibliography of Art (IBA), covering the years 2008 and part of 2009, and the Répertoire de la litterature de l'art (RILA), one of the predecessors of BHA, with records that cover 1975–1989.

The Bibliography of the Hebrew Book covers the national bibliography of the Jewish people: a detailed description of all the literature printed in the Hebrew alphabet, across the world in all languages. The Hebrew bibliography includes most of the books printed in Hebrew, Ladino, Yiddish, Judeo-Arabic and other Judeo languages found in Israel and worldwide, printed since the establishment of the Hebrew print (around the year 1460) till 1960. The Bibliography of the Hebrew Book also includes a short biography for authors, translators, editors involved in the Hebrew literary creation. The database includes more than 115,000 books and more than 15,000 short biographies.

BioMed Central is an STM (Science, Technology and Medicine) publisher of 270 peer-reviewed open access journals. The portfolio of journals spans all areas of biology, biomedicine and medicine and includes broad interest titles, such as BMC Biology and BMC Medicine alongside specialist journals, such as Retrovirology and BMC Genomics. The Max Planck Society is a BMC member and covers article-processing charges for Max Planck authors centrally. Further details are available on the MPDL website.

The Primary Sources platform consists of thematic collections of unique materials such as rare books and documents from around the world. These essential research tools in the area of humanities and social sciences are an integrated part of Brill’s product portfolio. Many of the collections are unique, as they are often the only source of rare documents outside of the source library itself. In addition to offering primary source material as collections, Brill also offer groups of collections as series.

CiteSeer is a scientific literature digital library and search engine that focuses primarily on the literature in computer and information science. CiteSeer aims to improve the dissemination and feedback of the scientific literature and to provide improvements in functionality, usability, availability, cost, comprehensiveness, efficiency, and timeliness in the access of scientific and scholarly knowledge.

Cogitatio is an academic and community-oriented publisher based in Lisbon, which was founded in 2014 with the aim of promoting the open access dissemination of scientific knowledge. Cogitatio currently publishes 4 peer-reviewed Open Access journals focusing on research in the social sciences and humanities. From January 1, 2023, the Max Planck Society covers article-processing charges for Max Planck authors centrally. Further details are available on the MPDL website.

Copernicus Publications has been publishing highly reputable peer-reviewed open access journals since 2001. Through interactive, multi-stage open access publishing, Copernicus aims to bring real transparency into scientific quality assurance. The Max Planck Society covers article-processing charges for Max Planck authors centrally. Further details are available on the MPDL website.

CORE’s mission is to aggregate all open access research outputs from repositories and journals worldwide and make them available to the public. In this way CORE facilitates free unrestricted access to research for all. We offer seamless access to millions of open access research papers, enrich the collected data for text-mining and provide unique services to the research community. CORE is providing a free API.

Data Europa EU is a central point of access to European open data from international, European Union, national, regional, local and geodata portals. The official portal for Euopean data consolidates the former EU Open Data Portal and the European Data Portal. Data Europa EU gives access and fosters the reuse of European open data among citizens, business and organisations. The portal promotes and supports the release of more and better-quality metadata and data by the EU’s institutions, agencies and other bodies, and European countries, enhancing the transparency of European administrations. Furthermore, it is intended to educate citizens and organisations about the opportunities that arise from the availability of open data. Currently, Data Europa EU contains more than 1.5 million European public sector datasets grouped by over 180 catalogues and pertaining to different topical categories.

Digi20 concentrates on the digitalization of monographs published in the second half of the 20th century, predominantly in the field of humanities and social sciences. In the first phase of the project, approx. 4,700 titles of programme segments of the publishers Vandenhoeck & Ruprecht, Wilhelm Fink / Ferdinand Schöningh as well as Otto Sagner were digitized. In a second phase, further approx. 1,750 titles are being included till 2014 by consecutively digitizing all monographs up to a defined ‘Moving Wall’ of three to five years to the current year of publication.

Since its foundation in 1964 the Max Planck Institute for European Legal History has been intensively engaged in research into the history of private law in Europe. It therefore has a particularly rich store of literary sources on 19th century German, Austrian and Swiss private and civil procedural law. With support from the German Research Foundation (DFG) it has been possible to digitize this exceptional concentration of material and make it available to a wider scientific audience. In the course of the project, which extended from 1997 until 2002, some 4,316 volumes were digitized comprising around 1,350,000 pages. For the Institute library this venture into digitization represents a continuation of its long-standing initiative to maintain and conserve its collections.

Dimensions is a linked research knowledge system that re-imagines discovery and access to research. Developed by Digital Science in collaboration with over 100 leading research organizations around the world, Dimensions brings together grants, publications, citations, alternative metrics, clinical trials, patents and policy documents to deliver a platform that enables users to find and access the most relevant information faster, analyze the academic and broader outcomes of research, and gather insights to inform future strategy.

The primary aim of DOAB is to increase discoverability of Open Access books. Academic publishers are invited to provide metadata of their Open Access books to DOAB. An overview of participating publisher can be found here.

The DOAJ service lists toll-free, quality controlled, scientific and scholarly journals. It generally aims at covering all subjects and languages. The DOAJ Articles Search is restricted to those journals the publisher has supplied article metadata for.

Edition Open Access provides open access to the publications of the Max Planck Research Library for the History and Development of Knowledge. The aim is to disseminate the results of scholarly work – in accordance with the open-access paradigm – to a broad audience rapidly and at low cost. The volumes presented here are directed at scholars and students in a wide range of disciplines. The works are available online both as print-on-demand books and open-access publications and can be accessed, together with additional information.

The EZB is a huge directory of electronic journals which mirrors the central Max Planck Society subscriptions as well as the local licensing situation of the institutes. Access rights to the contents of the individual journals are indicated with "traffic lights". Entries are searchable on journal level.

eLife publishes research in the life sciences and biomedicine, from the most fundamental and theoretical work, through to translational, applied, and clinical research. This includes subjects from human genetics and neuroscience to biophysics and epidemiology. The Max Planck Society covers article-processing charges for Max Planck authors centrally. Further details are available on the MPDL website.

F1000 Research is an open research and open access publishing platform, providing a suite of publishing services directly to researchers, research funders and institutions. The platform supports innovative features such as post-publication peer review, open peer review, and publication of negative results. The Max Planck Society covers article-processing charges for the open access journal F1000Research centrally. Further details are available on the MPDL website.