The chief executive of gambling firm Unibet, Petter Nylander, has been released on bail in France.
Mr Nylander says Unibet has always obeyed the law
Mr Nylander was arrested nine days ago following a complaint by France's state-owned gambling monopolies that Unibet was breaching French law.
He has been put under investigation, which is one step short of being charged and may not lead to a trial.
Unibet is registered in Malta, operates in Britain and is listed on the Stockholm stock exchange.
The European Commission disputes the legality of French gambling laws.
The French lottery operator Francaise des Jeux and horse-racing betting group PMU are protected by monopoly laws dating back to 1836 and 1891.
France issued a European arrest warrant for Mr Nylander after he failed to respond to an arrest warrant issued by a court in Nanterre in western Paris in April.
Mr Nylander was arrested in the Netherlands nine days ago while travelling to the UK. He was granted bail against a bond of 200,000 euros ($288,000; £139,000).
'Obeyed the law'
Unibet says it has 1.8 million customers in 150 countries.
Leaving the court in Nanterre, Mr Nylander said that Unibet had "always obeyed the law".
Two members of the European Parliament have objected to France's use of a European warrant to detain Mr Nylander, saying that the warrants were designed to help arrest people accused of violent crimes rather than those caught up in business disputes.
Unibet's cycling team was forced to withdraw from the Tour de France this year because French law prohibits advertising by foreign gambling firms.