Reports said the IP was linked to a helicopter company in Switzerland.
A Zurich-based company called Rega admitted that, as Schumacher's transfer from Grenoble to a Lausanne rehabilitation clinic was being arranged, it was contacted and Schumacher's medical file was passed on.
But the company, reportedly the major air ambulance operator in Switzerland, told AFP news agency that it believed "patient confidentiality had been preserved".
The Rega spokesperson added that it had "no knowledge of the investigation and had not been contacted by the authorities".
20min.ch, a Swiss website, quoted Rega spokesman Philipp Keller as saying: "Rega organised transport from Grenoble to Lausanne for a patient.
"As part of the organisation, a medical report was provided by the hospital in Grenoble."
Keller, however, said Rega only learned of the theft of Schumacher's records from the media.