Providers of very large online platforms and very large online search engines should take the necessary measures to ensure that researchers have access to the data, including access to publicly accessible data and, in accordance with proportionality and Union law on protection of personal data, access to specific datasets or categories of personal data to conduct independent research on systemic risks of their services. Such access should be granted in accordance with proportionality, with respect for the rights and legitimate interests of the provider and of the recipients of the service, and with due regard to the protection of personal data and the security of the service, and should enable researchers to conduct studies on the impact of the services on public security, civil rights and public health. Researchers may be individuals or representatives of research institutions, civil society organisations or public authorities, and should carry out their research in a transparent manner, including by publishing their findings. They should not be subject to unduly restrictive agreements with respect to the publication of their research. Researchers should have appropriate technical tools to extract and analyse data, and should observe appropriate confidentiality and data protection rules. The access to data shall be provided free of charge, unless the cost of providing that access would be disproportionately burdensome for the provider. Where a researcher wishes to obtain access to personal data, they should comply with Union law on the protection of personal data. In addition, providers of very large online platforms and very large online search engines should enable independent auditing of their algorithms, systems and tools used for content moderation and recommender systems, to assess the compliance of such algorithms, systems and tools with this Regulation and with Union law.