In August 2020, the Dutch ticketing service Ticketcounter inadvertently published a database backup to a publicly accessible location where it was then found and downloaded in February 2021. The data contained 1.9M unique email addresses which were offered for sale on a hacking forum alongside names, physical and IP addresses, genders, dates of birth, payment histories and in some cases, bank account numbers. Ticketcounter was later held to ransom with the threat of the breached being released publicly. The data was provided to HIBP by a source who requested it be attributed to redredred@riseup.net.

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