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, this study presents a novel approach that analyses over 700 agreements. Results suggest a strong growth in open access, from 4.3% in 2018 to 15% in 2022. Over five 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. Particularly, the OECD and BRICS areas revealed different publication trends. In conclusion, this study suggests that current levels of implementation of transformative agreements is insufficient to bring about a large-scale transition to full open access.

翻译：当前围绕转型协议的争议——这些协议旨在将基于订阅的期刊出版过渡至完全开放获取——突显了需要大规模研究评估这些协议对混合开放获取的影响。通过整合包括cOAlition S期刊检查器、Crossref和OpenAlex在内的多个开放数据源，本研究提出了一种分析700余项协议的新方法。结果表明开放获取呈现强劲增长，从2018年的4.3%上升至2022年的15%。五年间，11,189种混合期刊在8,146,958篇文章中开放获取了742,369篇（9.1%）。在此期间，能够利用转型协议的作者贡献了328,957篇开放获取文章（44%），并在2022年达到峰值——249,511篇开放获取文章中有143,615篇（58%）通过协议实现。虽然这一趋势主要由爱思唯尔、施普林格·自然和威利三大商业出版商推动，但开放获取的采纳情况在期刊、出版商、学科和国家间存在显著差异。特别是经合组织与金砖国家地区呈现出不同的出版趋势。总之，本研究认为当前转型协议的实施水平尚不足以推动大规模向完全开放获取的转型。