Red Bull acknowledge widespread Vettel interest
The 21-year-old recorded his and Toro Rosso's maiden victory at the Italian Grand Prix last month, and has scored 27 of Toro Rosso's 31 Constructors' Championship points this season.
Vettel has signed a deal with Toro Rosso's parent team Red Bull to partner Mark Webber in 2009, but Mateschitz suggests that other teams have already made enquiries.
"Half of the F1 grid is chasing him," Mateschitz told Austria's Salzburger Nachrichten.
"But Sebastian does not have any thoughts of moving out of Red Bull, nor have I. He is part of our family.
"We would be disappointed if he would propose to leave. However, he has earned a right for one of the best cars in one of the best teams, so we are obliged to offer him this at Red Bull Racing next season."