Jean-Claude Mas, the Frenchman who sparked a global health scare by selling substandard breast implants, was released from police custody on Friday and faces a charge of causing bodily harm, his lawyer said.
Mas will not be investigated for the graver charge of manslaughter, as was expected, but does now face criminal charges which carry longer sentences than those he faces in a fraud case expected to go to trial around October.
He was released on bail of 100,000 euros ($131,600), banned from leaving the country and from meeting former executives of his now defunct company Poly Implant Prothese (PIP).
"We are satisfied that Mr Mas could explain himself to a judge," his lawyer Yves Haddad said on iTele television. "This is a relief for him."
"On the charge of involuntary homicide, the judge decided that for now there is no link," Haddad said.
In the first arrests since the two-year-old scandal made headlines worldwide in December, Mas and a second PIP executive were seized at their homes in southern France just after dawn.
Women who have been campaigning against PIP since French authorities banned its products nearly two years ago welcomed the move as giving them a sense that the law was now in action:
"It's been too long," said Murielle Ajellio, who heads an association for women with implants. Up to now, she said: "You feel like you're fighting against the wind."
French authorities have been criticized for being slow to react to a case that has sown fear among tens of thousands of women who carry PIP implants. French inspectors ordered them off the market in March 2010, due to concerns over their quality.
But only last month did officials in Paris recommend their surgical removal, drawing attention to the problem for patients worldwide who had been fitted with products from the company, which was at one time the third biggest global supplier.
Lawyers for women in France who have filed complaints over PIP implants welcomed the arrests and said there must be no escaping justice for the 72-year-old Mas, who has been quoted as deriding those suing him as being motivated only by money.
"This is a comfort for the victims," said Laurent Gaudon, whose clients are pursuing PIP and surgeons who used its implants for fraud. "It's the feeling that justice is advancing and they have not been forgotten. It's the assurance that the guilty are at last going to be held accountable."
Philippe Courtois, who represents 1,300 people with PIP implants, said Mas should not be freed pending any trial.
Mas and PIP's former chief executive Claude Couty were questioned at home, as police conducted searches. They were then moved to police custody in the Mediterranean port city of Marseille, under the orders of prosecutor Jacques Dallest.
PIP enjoyed years of success with international sales, but behind the scenes employees, and Mas himself, have admitted to hiding from certification agencies the fact they were using cheap, industrial silicone, not approved for medical use.
Health authorities in France and elsewhere have stressed that PIP's products carry no proven link to cancer, but surgeons report that they have abnormally high rupture rates. Responses to the problem have varied among different foreign authorities.
Thursday's arrests follow an investigation opened in Marseille, close to PIP's former premises, on December 8 after the death from cancer in 2010 of a woman with PIP implants.
Mas and Couty can be held for up to 48 hours while a judge decides whether to open a formal probe and, if so, what bail conditions, if any, to set.
A trial date could be years away, given the extent of inquiry required, but the bodily harm case could make it harder for Mas to avoid appearing in court later this year on other charges of fraud and deception.
That latter case targets half a dozen former PIP executives and could also carry prison terms for them of several years. It has dragged on as investigators have had to quiz up to 2,700 women who have filed complaints over PIP implants.
Mas, who sold some 300,000 implants around the world, has acknowledged that he used unapproved silicone but dismissed fears that it constituted a health risk.
Earlier in January, leaks from a police document showed Mas admitting to lying about the quality of PIP's implants and describing the women filing complaints against him as just seeking money. The comments sparked public anger against him.
PIP closed down in March 2010 after regulators discovered it was using a non-approved, industrial silicone gel, and pulled its implants off the market.
Last month, the French government advised women with PIP implants to have them removed, and said it would pay for the operations in France, sparking alarm around the world.
France has called for tighter European Union regulations on medical devices in wake of the PIP affair, saying suppliers of prosthetics should require the same sort of authorization as manufacturers of prescription medicines.