A court in Marseille sentenced Jean-Claude Mas, the head of a French company accused of selling 300,000 faulty breast implants, to four years in prison.
He was accused of aggravated fraud for using industrial-grade silicone in the implants.
Mr Mas was also fined 75,000 euros (£63,000) by the court.
It is thought around 300,000 women were sold faulty breast implants, before the company went into liquidation in 2011.
47,000 British women had implants made by the company.
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