Nico Hulkenberg has split with his famous manager Willi Weber.
With the 69-year-old German, Hulkenberg made his promising Grand Prix debut at Williams last season but lost the seat for 2011 to the well-backed Venezuelan Pastor Maldonado.
He is now Force India's Friday test driver and hopes to be promoted to the race seat for 2012.
A statement on Hulkenberg's website said he will "from now on take management matters in his own hands", supported by his former PR advisor Timo Gans.
"Both sides are currently working on a smooth changeover and on a satisfying solution for everyone," the statement added.
German Weber also brought the Schumachers into Formula One but he no longer works with the brothers.