In what could be a classic illustration of the old saw about the right hand not knowing what the left hand is doing, Denmark issued nearly 300,000 passports over a four-year period before anyone noticed the encrypted code for stored fingerprints had reversed left and right.
From 2014 through 2017, until a member of the public reported the problem to authorities, no one noticed the error. Not the National Police, who in theory use the code to check against its database. Not Kube Data, which supplied the system.
The error was quickly fixed once discovered—but authorities are still pondering what to do about the 288,000 'wrong-handed' passports, and whether to re-issue them. Kube pointed out that they have not caused any inconvenience to travelers, and National Police affirmed to the press that "The passports are completely valid."