Japanese Man Lost a USB Drive With Entire City’s Personal Data After a Night Out

An average Tuesday bender turned into an unforgettable night.
japan, usb, flash drive, city, osaka, personal data, cybersecurity
The flash drive had data on the residents’ birth dates, addresses, and bank accounts, among other sensitive information. Photo: Dünzl\ullstein bild via Getty Images

Losing a wallet after a night out on the town is annoying. But losing a flash drive containing the personal information of about half a million residents? That’s nothing short of a headache, as one Japanese man would find. 

The unnamed man in his 40s had stored the USB stick in his bag when he went out for drinks at a local restaurant in Osaka prefecture’s industrial Amagasaki city on Tuesday. After several hours of boozing, the IT worker fell asleep on the street and by the time he woke up, the bag containing the flash drive was gone, local media reported.


Though the flash drive was encrypted, it contained the personal data of Amagasaki’s 465,177 residents, including their dates of birth, addresses, bank account numbers, and tax details. His company, BIPROGY, was hired by the city’s government to find out who in the city was eligible for tax exemptions.

“We deeply apologize to the citizens of Amagasaki, the city of Amagasaki, and all concerned for the inconvenience caused by the loss of important information entrusted to us,” the company said in a statement to local press.

Despite being known for its technological advances, Japan is notorious for its poor cybersecurity

In 2021, over five million people’s private data were leaked or lost in Japan, according to a survey by Tokyo Shoko Research, a company that collects information on Japanese businesses. Of those, nearly half were a result of computer viruses or unauthorized access. In March, the Japanese automaker giant Toyota Motor was brought to a standstill when a cyberattack on a supplier grounded domestic production. 

In the case of the missing flash drive, the employee had reportedly copied the city’s data onto a flash drive and took it to his company’s office—without permission—in order to continue his work there. 

Although the flash drive was found on Friday, the incident has angered many Amagasaki residents. The city office was inundated with 30,000 calls in one day after announcing the incident on Thursday.  

The employee found the USB drive, along with his bag, near an apartment building he vaguely recalls passing by during his night out, Japanese national broadcaster NHK reported. The city is trying to assess whether any data has been compromised.

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