"I want to ensure the future of our company. That is why, to ensure continuity, I have chosen the solution of foundations," Piech told the news magazine Focus.
Other press reports said the move would prevent a rapid sale of shares in the two auto manufacturers and guarantee that his wife, Ursula Piech, retained control of the fortune should the 73-year-old VW patriarch die.
Head of the VW supervisory board and grandson of Ferdinand Porsche, who founded the sports car maker and designed the VW Beetle, Ferdinand Piech is considered to be the one who makes strategic decisions at the car giant.
Austrian-born Piech plans to transfer his holdings to two foundations, Ferdinand Karl Alpha and Ferdinand Karl Beta, including a seven percent stake in the holding company that controls both Porsche and VW.
A 10 percent stake in the Salzborg-based Porsche Holding auto dealership company is also to be transferred to the Austrian foundations.
Ursula Piech, his fourth wife, is to take control of the foundations upon Piech's death, but would lose it again if she remarried. Ursula Piech is 19 years younger than Piech and was initially a care giver to his children.
According to Focus, some of the 12 children from Piech's four marriages do not agree with the arrangement and might contest it in court.
"Most of my descendants support me," Piech told Focus however.