(Bloomberg) -- Kenneth Dart, the billionaire investor based in the Cayman Islands, has increased his stake in British American Tobacco Plc, according to a filing Monday. 

Dart, 68, an heir to the eponymous plastic-cup fortune who renounced his US citizenship decades ago, now owns more than 10% of the London-based maker of Dunhill, Lucky Strike and Pall Mall cigarettes, the filing shows. The company has a market value of £51 billion ($64 billion). 

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Last week, British American shares fell as much as 10% after the company announced it was writing down the value of some US cigarette brands by about $31.5 billion. The stock has tumbled 30% this year. 

Dart disclosed a stake in British American in 2020, and has gradually boosted the size of his investment. He separately owns about 6% of rival tobacco firm Imperial Brands Plc. 

Dart has mostly avoided the spotlight as an investor, but gained some measure of infamy when Argentina’s former President Cristina Kirchner called him a “vulture” due to his investments in distressed sovereign debt and hardball negotiating tactics. He has a net worth of $6.4 billion, according to the Bloomberg Billionaires Index.

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