The EU and Switzerland list two possible birthdays for Sergei Korolev, who is first deputy director of Russia’s Federal Security Service (FSB). Both dates appear to be wrong, according to an investigation by The Kyiv Indepenent.
The EU and Switzerland say Korolev was born in either July or November, 1952.
Five other countries put his birthdate a decade later: July 25, 1962. That date is also listed in registration documents for a St. Petersburg apartment in his name, according to leaked residential data for the city. 
Peter Stano, a spokesperson on foreign affairs and security, said the E.U. uses “every relevant information at its disposal to identify precisely the individual or the entity to be added to the list of those subject to sanctions.”
“The date of birth is only one of the identifiers,” he said by email.
Stano did not explain why the EU lists two different dates, or why they are both a decade earlier than the birthday appearing on other sanctions notices.
Switzerland’s State Secretariat for Economic Affairs said its list of sanctions against Russia is identical to that of the EU.
“Deviations are being examined,” the secretariat said in a response to questions, but declined to provide more detail, saying it “does not comment on individual cases.”
The 1962 birthdate was also cited by an apparent former classmate of Korolev’s at the FSB Border Guard Institute. Reporters discovered a photo posted to Odnoklassniki, a social media site popular in Russia, showing a gathering of alumni including Korolev.
“On July 25, 2022, Sergey celebrated his 60th birthday,” the owner of the account wrote when posting a photo of the group, which was apparently taken in 2003.
The U.K., Australia, Ukraine, the U.S. and New Zealand all use the July 25, 1962, date in their sanctions notices for Korolev. Canada uses that year, but does not list a month or day.
Adding to the confusion, all three of Korolev’s names are spelled differently in various sanctions notices, due to differing transliterations from cyrillic.
Leaked flight records show travel by only one person with the name “Sergey Borisovich Korolev” born on July 25, 1962, indicating that this is the spelling of the name used in his passport.
However, only the Australian and U.S. sanctions notices use this spelling for all three of his names. Others spell his first name as “Sergei,” while both the U.K. and Canada spell his surname as “Korolyov.”
The FSB officer’s children use “Korolev” in their emails and social media accounts, providing further evidence that their father likely uses that transliteration too.
The EU and Swiss sanctions also use “Korolev.” But they use “Sergei” instead of Sergey, and they add an extra “s” to spell his middle name as “Borissovich.”
Depending on the country, sanctions against Korolev include restrictions on access to assets, investments and travel. The different spellings and birth dates listed for Korolev could allow him to escape such restrictions, according to Vladyslav Vlasiuk, Ukraine’s presidential commissioner for sanctions policy.
“This leaves wiggle room,” he said in an interview. “The sanction remains, but some banks, for example, might not recognize this person as sanctioned, especially if there is no other identifying data.”
There is no evidence that Korolev has financial interests outside Russia, although he did send his children to pricey English language courses in the U.K. and Switzerland. The children appear in photos on the websites of London’s Harrow School, and the American Tassis School in the Swiss village of Montagnola.
As one would expect of a spy, Korolev’s background is shrouded in mystery. But OCCRP and iStories reported in 2021 that he has personal connections with several well-known leaders of the Russian criminal underworld who have been accused of kidnappings and contract murders.
