Dear colleagues, After our accidental deletion of RPKI ROAs on Wednesday evening, we have a post-mortem report to share with the working group. Following an update to our internal registry software on 1 April at 18:16 (UTC+2), 2,669 ROAs were deleted from Provider Independent (PI) address assignments. This was caused by our registry software classifying these assignments as not-certifiable. From our logs, we can confirm that these blocks never left the RIPE Registry, and within 15 minutes the registry was back to normal. However, by that time the ROAs had already been deleted and could not be restored without intervention from our engineers. Affected users with alerts set up in the LIR Portal received a notification email on 31 March at 22:23, stating that their ROAs were missing. Some of these users emailed our Customer Service Department to ask why their ROAs had been deleted. As this was outside of office hours, our staff did not discover the issue until the next morning. Our engineers were able to reinstate all of the missing ROAs by 13:15 on 2 April. We then informed our membership via ncc-announce and notified the affected users directly. We have since implemented stricter checks on both our registry and RPKI software. We are also investigating whether any of these PI assignments suffered from route-leaks or hijacks after their ROAs were deleted. We apologise for any inconvenience this may have caused and we are taking all necessary steps to ensure this does not happen again in the future. Kind regards, Nathalie Trenaman Routing Security Programme Manager RIPE NCC