Three years after the skiing accident that left him seriously injured, seven-time Formula One world champion Michael Schumacher is slowly being dropped by the personal sponsors who backed his career in motorsport.

This week Maquina do Esporte, a Portuguese-language sports marketing publication, claimed that two more sponsors have backed out out of their deals with the stricken racing legend.

Luxury watchmaker Audemars Piguet and German door manufacturer Hormann have now pulled their backing, and a line of Audemars Piguet watches in honour has reportedly been withdrawn from the collection.

Jet Set, Navyboot, Rosbacher and Erlinyou have already withdrawn their sponsorship, while the report claims that "others have negotiated a reduction" in the amount paid to the former Benetton, Ferrari and Mercedes driver.

Schumacher's most loyal and main backer remains Deutsche Vermongensberatung, which is also strongly supporting his son Mick's climb up through the ranks of world motorsport.

According to The Sun, the seven-time world champion has already spent around £13.8 million (approximately $16.8 million) in medical bills ever since he had the accident three years ago, based on the alleged £115,000 per week cost that his treatment requires.

There have been no recent updates on Schumacher's condition. Sabine Kehm, Schumacher's manager, told The Mirror newspaper before Christmas that the family will not say anything yet about Schumacher's condition as his current state "is not a public issue."

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