1.    Introduction

Transformative agreements, also known as ‘read and publish’, or ‘publish and read’ deals, have been an important strategy in the transition to open access in the past decade. “Transformative agreement” is an umbrella term describing those agreements negotiated between institutions (libraries, national and regional consortia) and publishers in which former subscription expenditures are repurposed to support open access publishing of the negotiating institutions’ authors, thus transforming the business model underlying scholarly journal publishing” (ESAC n.d.). The number of transformative agreements concluded has increased significantly from 2015 onwards. In 2025 almost 1.200 of such agreements were included in the ESAC-registry, 340 of which were current contracts (ESAC n.d.).

While important steps have been taken to improve the transparency of these agreements, much remains to be desired. For example, although many of the contracts are publicly available, it is often unclear how the overall prices of these contracts are structured: how much is paid for publishing, how much for reading (European Commission, 2024)? Also, none of the existing agreements provide article-level data about which articles are covered by the agreements and which are not. This data is only made available to the libraries and/or their consortia, provided by the publishers but often not shared publicly. This lack of data and transparency makes it difficult to analyse the impact of these agreements and to inform critical reflection on their role in the transition to OA.

In this article, we present a method for calculating which articles have been covered by transformative agreements by using exclusively open metadata sources. The sources used are the Journal Checker Tool as developed by cOAlition S¹ in combination with corresponding institution data from OpenAlex (Priem e.a., 2022). The openness of this data allows everyone interested to determine from a given corpus of publications whether or not they were likely covered by a transformative agreement, without having access to the actual publisher’s data. To demonstrate the potential use of the method, we apply it here to a dataset of publications funded by the Dutch Research Council NWO and its sister council for health research ZonMw.

Additionally we have been able to validate this method by comparing the figures obtained using this open method with the actual figures as reported by the publishers to the Dutch library consortium UKB. Making this comparison shows that our open method leads to reasonably reliable results: 89% of publications were rightly identified as having been covered by one of the transformative agreements that are in place in the Netherlands. The error rate of 11% raises interesting caveats to our approach. While we know the Journal Checker Tool has been used before to study the impact of transformative agreements (Jahn, 2025), to our knowledge this is the first time this approach is validated by actual publisher data on transformative agreements.

2.    Transformative agreements

A transformative agreement is a contract between a publisher and an institution (often the library or a consortium of libraries) to transform subscription-based scholarly publishing towards open access (Borrego et al., 2021, Bakker et al,. 2024, Jahn, 2025). Transformative agreements come in many different forms and are also known under “offsetting”, “read-and-publish” or “publish-and-read” deals. While offsetting, R&P and P&R deals do not necessarily have the goal to achieve a full transformation to open access, this is the intended goal of transformative agreements. Under these agreements institutions seek to negotiate reading access to the publisher’s subscription-access publications as well as open access publishing of works by authors affiliated with the institution. Typically only corresponding authors of an institution are eligible to publish open access under transformative agreements (Schimmer et al., 2015, Jahn, 2025).

The concept behind transformative agreements is “that there is enough money in the system” to fund a full transition from subscription to open access publishing (Schimmer et al., 2015). Transformative agreements were thought to provide traditional publishers the time to gradually transform their business model from subscription to open access by gradually offsetting the “read” to the “publishing” income (Prosser, 2003). An important characteristic therefore of transformative agreements, is their time-limited, temporary and transitional nature (ESAC, Guidelines for transformative agreements. n.d.).

The first transformative agreements, although not named like that at the time, date back to the early 2010’s. In 2012 the Royal Society of Chemistry (RSC) announced its “Gold for Gold” model. In 2014 the Austrian library consortium Kemö negotiated its first transformative agreement with IOP Publishing. After having participated in a pilot programme for Springer Open Choice from 2007-2012 (Schmidt & Shearer, 2012), the Association of Universities in the Netherlands (UNL) negotiated its first transformative agreement with Springer in 2014, later followed by similar deals with Wiley and Elsevier and other big and medium sized publishers (Borrego et. al., 2021, IOP Publishing, 2014).

The concept of transformative agreements was highly supported by the OA2020 initiative which brings together the community of national and/or regional negotiation teams from many countries (https://oa2020.org/). Transformative agreements have also benefited from the support by cOAlition S, the consortium of funders including the European Commission behind Plan S. In their guidance to the implementation of Plan S they announced that a variety of “transformative arrangements” would be considered compliant with their policies, transformative agreements between publishers and libraries or their consortia being one of them (Coalition S, n.d.). More specifically they stated that publication in hybrid journals was not supported, except as part of transformative arrangements and only for a limited time (Schiltz, 2018).

The number of transformative agreements has increased significantly over the years. In January 2025 almost 1,200 agreements had been registered in the ESAC-registry, the most comprehensive source of information about these agreements.² Whereas the majority of these agreements are from consortia in Western Europe, agreements are being negotiated in other parts of the world as well. Most notably the US, Canada, Australia, Japan, Turkey and Saudi Arabia. Recently, the first transformative agreements have been negotiated in Latin America by the Colombian library consortium (Muñoz-Vélez, 2024).

Challenges and gaps

Despite the growing number of transformative agreements being negotiated, controversies persist. Some have argued that continued reliance on big deal type deals with the bigger publisher perpetuates market concentration (Earney, 2017, Butler, 2023, Shu & Larivière, 2023, Rothfritz et. al., 2024, Jahn, 2025). Others have called into question whether transformative agreements are an effective way to control costs and actually lead to reduced pricing (Borrego et al., 2023, Schmal, 2024). It has been argued that transformative agreements increase the inequity in the global science system because only institutions from high-income countries are able to afford transformative agreements (Ross-Hellauer, 2022, Else, 2024). Most importantly the transformative nature of the deals has been called into question because substantial transition of hybrid journals to full open access could not be observed (Matthias, 2019, Momeni, 2021, Kiley, 2024). In Sweden calls can already be heard to move away from transformative agreements (Widding, 2024).³ In its large-scale review of transformative agreements in the UK by JISC, it is concluded that while transformative agreements have contributed to making more UK research open access, the transition is slow. Based on the current rates it is estimated that it would take the five big publishers another 70 years to flip all of their titles to full open access (Brayman et al., 2024). Also cOAlition S has been reevaluating its support for transformative arrangements. Failure of publishers to meet their target in transitioning their journals to full open access, has already led cOalition S to terminate its ‘transformative journal’ programme. Also the financial support for transformative agreements has been discontinued in 2024, for those funders that contribute to these deals (COAlition S, 2023). Although publishing through a Read and Publish deal will continue to be considered a Plan S compliant.

With the growth of transformative agreements being negotiated, also the transparency of these deals has increased. The ESAC initiative has contributed to this significantly, most notably with the ESAC Transformative Agreement Registry which is a voluntary register of agreements. It contains basic information about a large number of agreements and for many (although certainly not all) of them links to a fully publicly available version of the contract. However, even if a fully disclosed and published version of a contract is available, the financial information often remains patchy and in some cases by no means easy to trace. While many contracts do indeed disclose the total cost of the contract, far fewer include details on the split between reading and publishing costs, and how this is determined (European Commission, 2024). In addition, there are varying models in use in these agreements regarding the number of publications covered, making an estimation of per-article costs for open access publishing especially difficult.

Another major gap in the information about transformative agreements is article-level data identifying which articles are covered by the agreement. The contracts listed in the ESAC-registry often do contain lists of journals but information on which articles are covered by an agreement is not publicly available for any of the agreements.

This data is reported by the publishers to the libraries and/or their consortia but data from these publisher reports is not shared openly.⁴ This lack of data makes it hard to analyze the impact of transformative agreements and leads to a persistent critical assessment of these deals going forward.

In the absence of hard, openly available article-level data on transformative agreements, we present in this article a method for calculating the number of articles that could have been covered by transformative agreements. We do that by using publicly available metadata sources. With this method it is possible to determine with a reasonable amount of certainty which publications from a given corpus were covered by a transformative agreement and hence which publications were likely paid under a transformative agreement. We will apply our method to a set of publications funded by the Dutch Research Council NWO and the Netherlands Council for Health Research ZonMw. We will also assess the validity of this approach by comparing with data provided to us by the Dutch Library Consortium UKB. UKB has been responsible for negotiating transformative agreements since 2015. Part of these contracts is the obligation of the publishers to provide reports on publications that were made available in open access under these agreements. By comparing data from these publisher reports with data obtained by our open method, we are able to assess the reliability of this open approach. While we know this method has been used before, notably by Jahn (2025) in his large-scale study on hybrid journals in transformative agreements, this is the first time it is validated with actual data from publishers.

3.    Method

Central to our approach of determining whether a publication could have been covered by a transformative agreement, is the Journal Checker Tool as developed by Coalition S.⁵ Aim of this tool is to provide grantees funded by cOAlition S funders with information about whether publishing in a specific journal is compliant with Plan S. To that end, authors are requested to enter a journal name, the name of their funding agency and their affiliation. The tool then calculates which route to compliance for that specific combination is available. Using the ESAC-registry as a source, the Journal Checker Tool collects journal-level data about transformative agreements that are in place, which journals are included in these agreements and which institutions have subscribed to these agreements. The data from the Journal Checker tool is exposed through a publicly available API.⁶ It used ISSN (more precisely ISSN-L) to identify journals and RoR-IDs to identify institutions.

Typically, publication under a transformative agreement is only open to the corresponding authors affiliated with the institution subscribing to that agreement. In order to determine whether a publication can be covered by a transformative agreement, therefore it is necessary to identify the corresponding author. Identifying corresponding authorship is associated with several challenges (Chincilla-Rodríguez, 2024). Earlier studies have therefore taken first authorship as a proxy to determine eligibility for transformative agreements (Haucap, 2021, Shu & Larivière, 2024, Zhang, 2022, Jahn, 2025). Recently, however, OpenAlex has enriched its open bibliographic database with the field “corresponding_institution_ids”. It provides a list of institutions (identified by OpenAlex ID) for those authors that are listed as corresponding authors in the metatext of a work. According to the documentation this feature is still under development.⁷ Currently 44% of the journal articles with publication year 2023 in OpenAlex have corresponding_institution data.

By combining the various metadata elements for a given DOI it is possible to determine whether a publication could have been covered by a transformative agreement. Figure 1 presents the workflow needed to enrich the metadata of a given DOI record and check whether it could (should) be covered under a TA.

Figure 1. Workflow used to enrich a given DOI record.

Important limitations to this approach that have to be listed are the following. The Journal Checker Tool only provides journal-level information for the current transformative agreements and not for contracts that have expired. This is understandable for the specific purpose of the tool: authors seeking guidance on the compliance of the journal of their choice should be informed about currently (in)valid options. Information about agreements that have expired are deleted which means retrospective studies as presented here will inevitably result in false-positives and false-negatives. Also, information on participating institutions is not fully harmonized, and ROR IDs are not included for all institutions.

With regards to the use of institutional affiliation data from OpenAlex it has to be acknowledged that information on corresponding authors is relatively new, and might not yet be stable regarding coverage and quality (Zhang et al., 2024).

4.    Use Case

Transformative agreements have been a central element of the open access strategy in the Netherlands (Bosman et al., 2021). These are negotiated by the consortium of Dutch university libraries and the Royal Library (UKB) together with the Association of universities in the Netherlands (UNL). Some, however, are negotiated by individual institutions in the Netherlands. The first agreements date back to 2014.

They have been renegotiated and updated regularly over the years. Currently 22 agreements are in place, mainly serving researchers at the Dutch universities.⁸ Researchers employed by the 20 independent research institutes under the umbrella of NWO and the Royal Academy KNAW are usually excluded from these deals.

NWO is a founding member of cOAlition S and has aligned its open access policies with Plan S in 2020 (NWO, 2020). Unlike funders in some other European countries, the Dutch Research Council does not financially contribute to transformative agreements. However, following the principles of Plan S, publications published under one of the transformative agreements are considered to be compliant with the open access policy of NWO, as well as its sister council ZonMw. Article-level data on which publications are covered by transformative agreements are not publicly available. This data is provided to the UKB consortium by the publishers but is not made available to the funders. This makes it challenging to assess whether publications are in compliance with the funders’ open access requirements. For the moment therefore, all publications in hybrid journals under the correct CC BY license (CC BY and CC BY ND) are considered to be compliant.

From a policy perspective it is still interesting to know what the effect is of the transformative agreements negotiated in the Netherlands on the open access status of NWO/ZonMw funded research. Do the agreements adequately cover the research funded by NWO and ZonMw or are there still gaps in the portfolio of agreements?

What is the share of publications funded by both funders covered by the transformative agreements? The above presented method was developed to at least partly answer these kinds of questions.

In what follows, we will show how this method can answer the following research question:

• What is the share of publications published in 2023 and funded by the Dutch Research Council NWO and ZonMw that were (likely) covered by one of the transformative agreements in place in the Netherlands?

Answering this question, begins with identifying the corpus of publications that is the result of NWO/ZonMw funding. For the purpose of this use case we collected and deduplicated publication data from three sources: Crossref (Hendricks, 2020) and the grant management systems of NWO (ISAAC) and ZonMw (MyZonMw):⁹

• data from Crossref were selected by means of the Crossref funder ID for both NWO (10.13039/501100003246) and ZonMw (10.13039/501100001826) and the funder IDs nested under this hierarchy. In addition we queried Crossref using NWO’s and ZonMw’s acronyms. Many more name variants are circulating but can not be easily queried using the Crossref API.

• To this corpus we added publications registered by grantees funded by NWO and ZonMw in their grant management systems ISAAC and MyZonMw. We only included publications with a DOI and publications with a publication date in 2023, based on Crossref.

Figure 2. Methodology of deduplication of (open) metadata sources and open indexes used for analyses.

After deduplication and exclusion of non-article material we ended up with a dataset of 6,610 articles. Using a script written in Google Apps Script this dataset was further enriched with metadata from Crossref, Unpaywall and OpenAlex:

• Basic metadata of all records, including ISSN and publisher information from Crossref.

• Information about the open access status for all records was retrieved using Unpaywall.¹⁰

• OpenAlex was used to add the number of corresponding institutions, their names and ROR-id’s for all records.

Finally, a Google Apps Script (De Jonge, Kramer & Sondervan, 2025) was used to parse all records through the Journal Checker Tool using the ISSN-L and ROR-ID variables to determine whether the publication was covered by a transformative agreement or not.

5.    Results

A total number of 6,610 articles were identified as being published in 2023 as the result of NWO/ZonMw funding. Using the information from the Journal Checker Tool 2,304 of these publications (or 34% of publications from our dataset) could potentially have been covered by one of the existing transformative agreements.

6.    Validation

With the method described above we have been able to calculate – with a reasonable amount of certainty – the number of publications that were covered by transformative agreements. Because it makes use of metadata from open APIs this method is available to everyone interested to study the impact of transformative agreements on a given corpus of publications. In what follows we will show that this method is indeed reasonably reliable. We do so by comparing the figures obtained via our “open method” with actual publisher data for these publications provided to the Dutch library consortium UKB. While we know the data underlying the Journal Checker Tool has been used before to study the impact of transformative agreements (Jahn, 2025), this is the first time this approach is validated by actual publisher data on transformative agreements.

UKB is the Dutch Library consortium consisting of the 13 Dutch university libraries and the National Library of the Netherlands (KB). It has been responsible for negotiating collective license agreements for the Dutch universities since the 90’s. From 2015 onwards many of these agreements included open access publishing elements. In 2023 a total number of 20 transformative agreements were in place. To support these negotiations the UKBsis datahub was developed, containing data from more than 400,000 journal articles from Dutch institutions published since 2018 (Schalken, 2022). It combines data from a broad range of different sources including Scopus, Crossref, OpenAlex, OpenAIRE, Unpaywall, DOAJ, OpenAPC and OASwitchboard.¹¹ Most importantly, it also collects article level metadata on articles that were published as part of transformative agreements negotiated by the consortium. This data is provided by the publishers according to specific requirements set in the contracts between the publishers and the consortium.

Comparing the data presented in the previous section with the actual publisher data, allows us to evaluate the reliability of this method. Figure 3 shows the results of this exercise.

The main conclusion that can be drawn from this comparison is that 89% (2,054 out of 2,304) of the articles were correctly attributed to a transformative agreement. For 250 articles, the attribution could not be validated using UKBsis data: according to the publisher data provided to the consortium, these publications were actually not published under an agreement, resulting in an error rate of 11%. Of these publications, 233 (category b; Figure 3) could be retrieved from the UKBsis datahub, allowing a closer examination of these publications.The following reasons were found to be the most important reasons why these publications were not published under a transformative agreement:

• A publication had multiple corresponding authors, not all of whom were eligible for publication under the agreement, or corresponding authors had multiple affiliations but appeared to use one that made the publication ineligible for the agreement. It should be noted that in most of these cases the open metadata provided by OpenAlex correctly matches the affiliations in the paper, but the UKBsis datahub appears to have had more detailed information regarding eligibility.

• A transformative agreement was in place, but apparently the authors chose not to use it. Articles in this category were published closed or via the green or bronze open access route.

• A transformative agreement was in place, but the agreement was capped, meaning that authors could no longer make use of the agreement at the time of publication.

• A transformative agreement was in place at the time of analysis (2024) but not at the time of publication (2023).

• The article type (e.g. letters to the editor) is not eligible under the deal.

• A transformative agreement was in place, but was negotiated at the institutional level rather than the consortium level. Publisher data on these agreements are not included in the UKBsis datahub and are therefore not recognised as covered by any of the national deals.

It should be noted that a subset of publications (n=176) identified by us as having NWO- or ZonMW funding, and publication year 2023, either lacked funding information in UKBsis, or were in UKBsis with a different publication year. We included these publications in the figure above in category b or c, depending on whether they were listed as being part of a transformative agreement in UKBsis.

A very small set of publications (n=17) were wrongly ascribed to a transformative agreement and could not be retrieved from the UKBsis datahub at all. A manual check showed that any of the reasons given above could have been reasons that indeed none of these were published under a transformative agreement.

We have also looked at the publications that according to the UKBsis datahub were published as part of one of the transformative agreements but were not detected using our open method. In total UKBsis identified 3,907 publications published in 2023, in which funding from either NWO and/or ZonMw was acknowledged and that were published as part of a transformative agreement. Therefore, 1,853 publications were ‘missed’ using our open method. Two main reasons can be mentioned for this:

• 717 publications were part of a transformative agreement but not picked up by our open method because the corresponding author was not recognized by OpenAlex as being affiliated with one of the Dutch institutions.

• 1,136 publications were published as part of a transformative agreement, but were not part of our original dataset because they were not identified as funded by NWO or ZonMw. This can be explained by the fact that the UKBsis data hub has richer funding metadata, not only from Crossref but also from Scopus and OpenAIRE.

In summary, 89% of articles in our dataset were correctly assigned to transformative agreements using our open method, showing that it indeed is a reasonably valid approach. 11% were attributed incorrectly. For a significant portion of these publications a transformative agreement was actually in place, but was not used for various reasons. Additionally, 47% of publications identified by UKBsis were missed by our open method, primarily due to unrecognized author affiliations in OpenAlex and gaps in the availability of funding metadata in Crossref on which two of the authors have reported before (Kramer & De Jonge, 2020).

7.    Concluding remarks

Transformative agreements are an important part of the transition to open access in many countries. While research has shown that transformative agreements have an impact on increasing the number of open access publications in certain countries (Pinhasi, 2020, Jahn, 2022, Jahn, 2025), they are not without controversy. In recent years, important steps have been taken to make these agreements more transparent. For many of them, at least the contracts are open and publicly available on the ESAC register. What is seriously lacking, however, is openly available article-level metadata identifying the articles covered by these agreements. Without this data, it is very difficult to determine which publications are covered by these agreements and which are not. This makes all kinds of follow-up research impossible, such as research on the uptake and impact of transformative agreements for specific countries, or research on the costs associated with transformative contracts (Jahn, 2025).

Data on publications published under transformative agreements are of course made available to libraries and/or their consortia, but usually not openly shared or made available. Apparently, as we can learn from the study by Marques et al. (2019), there is also great diversity in the type of metadata that library consortia request from publishers and that publishers report.

This article offers a method to address this lack of metadata. We present a method for determining whether or not a given corpus of publications is (likely to be) covered by a transformative agreement. To demonstrate its potential, we have used this approach to analyse the proportion of publications published under a transformative agreement resulting from NWO and ZonMw funding. By comparing the results of this analysis with actual publisher data reported to the Dutch library consortium UKB, we were able to confirm that this open method is indeed reasonably reliable: 89% of the publications were correctly attributed to one of the transformative agreements available to researchers in the Netherlands. The 11% false positives shed an interesting light on the limitations of this method.

Our method uses public APIs to collect the necessary information. The advantage is that the method can be easily replicated for other situations and contexts, for example by institutions or funders who want to analyse how many papers affiliated to their organisation have been published openly as a result of transformative agreements. The method presented in this paper can determine with a reasonable degree of certainty whether a publication was covered by a transformative agreement.

Of course, in line with open science principles and initiatives like the Barcelona Declaration (Barcelona Declaration, 2024), it would be better if article-level metadata about publications covered by transformative agreements were openly shared by the publishers and/or libraries that negotiated these transformative agreements. Given its central role as the most comprehensive source of information on transformative agreements, we think ESAC would be the most appropriate infrastructure to deposit this data. Libraries or their consortia would probably be the most obvious organisations to take that responsibility. Alternatively, publishers could be asked to deposit this information as part of the article metadata with Crossref; their metadata schema currently does not support this but it could in the future.

In the meantime, the method presented in this paper provides a reasonably reliable approach to track transformative agreements and critically evaluate their contribution to the transition to open access.

Acknowledgements

The authors wish to thank the Dutch Library Consortium UKB for their permission to use and share data from the UKBsis datahub and Arjan Schalken (Free University Amsterdam, program manager UKBsis) and Maaike Koperdraad (Utrecht University Library, data steward UKBsis) for help with the analysis.

Author contributions 

CRediT: HDJ: Conceptualization, Data curation, Formal Analysis, Methodology, Software, Visualization, Writing – original draft; BK: Data curation, Formal Analysis, Methodology, Software, Visualization, Writing – review & editing; JS: Data curation, Methodology, Writing – review & editing.

Competing interests 

The authors declare no competing interest. The authors write in a personal capacity and views they share in this article do not necessarily express the opinion of their employers.

Funding information 

The authors did not receive any funding for the research reported in this paper.

Data availability

The data and code used in this study are available at https://doi.org/10.5281/zenodo.15000633 (De Jonge, Kramer & Sondervan, 2025):

• Data set of unique DOIs (n = 6,610) enriched with data from Crossref, Unpaywall, OpenAlex and the Journal Checker Tool.

• Google Apps Script for retrieving information from the Journal Checker Tool API.

• Data set of DOIs (n= 10,126) retrieved from the UKBsis datahub and used to establish the overlap with the original dataset.

Footnotes

¹ www.journalcheckertool.org

² https://esac-initiative.org/about/transformative-agreements/agreement-registry/. See Rothfritz et. al. (2024) for a comprehensive analysis of all contracts registered until August 2024.

³ https://www.su.se/english/news/open-access-need-to-move-away-from-transformative-agreements-1.683787

⁴ Elsevier being a notable exception as it includes article-level invoicing metadata in its XML full-text. See Jahn et al. (2022).

⁵ www.journalcheckertool.org

⁶ Documentation on the API can be found here: https://journalcheckertool.org/apidocs/

⁷ https://docs.openalex.org/api-entities/works/work-object/authorship-object#is_corresponding

⁸ An overview of publisher deals can be found on www.openaccess.nl. Last accessed on January 28 2025.

⁹ https://www.nwo.nl/en/grant-application-system-isaac

¹⁰ www.unpaywall.org

¹¹ https://ukb.nl/en/programmes/ukbsis/

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