Michael Schumacher did not reduce his speed significantly after going off-piste prior to his accident, French prosecutors said.
The investigators said the Formula One champion tried to reduce his speed, before one of his skis hit a rock, causing Mr Schumacher to fall.
The investigator added that Mr Schumacher was following the rules imposed in the French resort.
The racing driver, who suffered a severe head injury while skiing off-piste in the resort of Meribel in France last Sunday, remains in an artificially induced coma.
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