Maastricht University paid 30 bitcoin ransom for encrypted files on December 23, 2019. Attack targeted 267 Windows and Linux servers and 7,307 workstations. University says all critical systems now have online and offline backups to avoid facing a future total failure scenario in the event of another ransomware attack. University paid the ransom to have the files decrypted on December 30 after closely analyzing the options including rebuilding all infected systems from scratch or creating a decryptor to avoid having to rebuild all the compromised systems.
Source: https://www.bleepingcomputer.com/news/security/ta505-hackers-behind-maastricht-university-ransomware-attack/