Banks' cyber defenses are no match for an employee who sleeps on the job.

A worker at an unnamed German bank unintentionally transferred $293 million in April 2012 after falling asleep at his keyboard, according to testimony on Monday in a court in the German state of Hesse.

The man had been asked to transfer $82 from a bank account that belonged to a retiree but "fell asleep for an instant, while pushing onto the number 2 key on the keyboard," according to Agence France-Presse. Press reports did not give the name of the bank.

That sleeptyping transformed the total from 62.4 euros into 222,222,222.22 euros.

The bank later discovered and corrected the error, then fired the employee's supervisor for failing to catch the mistake.

The court took testimony that on the day of the compound keystrokes, the supervisor, who sued for her job, had inspected 812 records for errors, with most demanding about a second of scrutiny, the BBC reported. The court reinstated the supervisor after finding no ill intent on her part and concluding that she should have received a warning.

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