The luxury apartments at One Blackfriars are billed as some of London’s most prized properties, with sweeping views of the city’s major attractions from the banks of the River Thames.

Recent filings show Silicon Valley billionaire Yuri Milner is the mystery figure behind a Cayman Islands-based entity that acquired a penthouse at the 50-story development for £57.6 million ($70.3 million) in 2021.

The 61-year-old is best known for placing lucrative early bets on tech giants such as Meta Platforms Inc. and Airbnb Inc. through his investment firm, DST Global. He’s listed on documents filed by MFRD Property Holdings as the person with “significant” control over the entity that acquired the apartment.

The purchase was a vote of confidence in London’s luxury real estate market, which was roiled by the Brexit vote before beginning to recover during the pandemic. Home values in London’s tonier districts rose 2.3% in the 12 months through August, according to researcher LonRes, bucking a wider downturn.

Moscow-born Milner, who renounced his Russian citizenship last year after Vladimir Putin’s Ukraine invasion, has a net worth of about $3.8 billion, according to the Bloomberg Billionaires Index. He was the most prominent tech leader seeking to distance his firm from Russia following the war and DST has publicly condemned the attack.

A representative for MFRD said the money for the home purchase came through a trust funded by the Israeli citizen and that the property was bought for investment purposes. The trust’s beneficiary is a charitable foundation for scientific and humanitarian purposes, and the apartment is rented out with the income going to the nonprofit entity, the representative added.

The investor also keeps a base in the US, where he previously bought a house for $100 million in Los Altos, California. Milner pays market rates when he stays at the London property, the representative said. One penthouse at the development is currently available to rent for £14,950 a month.

The Milners are signatories to the Giving Pledge, under which wealthy people pledge to contribute a majority of their wealth to philanthropic causes.

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The family’s charitable initiatives include the Breakthrough Prize Foundation, which aims to recognize leading scientists. Alphabet Inc.’s Sergey Brin and Meta Chief Executive Officer Mark Zuckerberg are among its other founders.

The foundation committed $100 million in funding last year to support refugees from Ukraine and elsewhere.