British trader Sanjay Shah has landed in Denmark after being extradited from the United Arab Emirates (UAE) over tax fraud charges worth £1.46bn.
Mr Shah, who lives in Dubai, is accused of participating in fraudulent share trading schemes.
He was arrested by Dubai police last year following the Danish investigation into Solo Capital, a hedge fund that he founded.
Mr Shah denies the charges and insists that the trades were legal.
Denmark is one of the countries hardest hit by so-called "cum-ex" schemes, although they also flourished in Germany and Belgium. The scam involved rapidly selling shares between investors in order to create confusion over who owned the shares at the time a dividend was paid out.
Tax on the dividends was subsequently reclaimed by multiple parties, although it was only paid once.
Denmark says Mr Shah's Solo Capital ran fraudulent schemes for companies and investors between 2012 and 2015. Mr Shah is the primary suspect in the Danish case of tax fraud.
The money Danish authorities are seeking to recoup amounts to some 12.7bn crowns (£1.46bn; $1.84bn; €1.7bn) - nearly 0.5% of the country's entire GDP.
"This is one of our biggest and most serious cases of financial fraud," Justice Minister Petter Hummelgaard said.
Prosecutors will ask for Mr Shah to be held in custody until the start of his trial, scheduled for January next year.
After Mr Shah lost his job as a trader during the 2008 financial crisis, he founded Solo Capital and moved to the UAE. In Dubai, he led an extravagant lifestyle, including living on the exclusive Palm Jumeirah island. Musicians who played for an autism charity he founded included Elton John and Drake.
He bought two yachts, naming them the Solo and Solo II.
But since 2020, he has been doggedly pursued by Danish authorities over the fraud charges. Much of Mr Shah's fortune, including a £15m central London property, has been frozen.
Last month, in a separate case, Mr Shah lost a bid in the UK Supreme Court to block Denmark from pursuing him in English courts.
Also in November, British national Guenther Klar, who worked for Solo Capital between 2010 and 2012, went on trial in Denmark in the country's first court case over cum-ex fraud.
Mr Klar, who was extradited from Belgium, is accused of defrauding the government of some 320m Danish crowns (£37m). He denies wrongdoing.