Williams' share price has plummeted amid the famous British team's worst-ever start to a new Formula One season.
The Oxfordshire based team floated co-owner and long time technical boss Patrick Head's shares on the Frankfurt market prior to the start of the 2011 championship.
The Guardian reports that the price is now 27 per cent lower.
The big loser is Dutch investor Cyrte, who bought 5 per cent of Williams. It's share is now worth EUR 3.3 million less.
Sponsorship consultant Julian Cottam is pessimistic.
I didn't see why Patrick Head was so determined to offload his entire stock
"I can't see any motivation at all for a brand to align with a team that has made such a fundamentally flawed decision," he said.
"I didn't see why Patrick Head was so determined to offload his entire stock in the business at a time when Williams has had a long period without any great success on track," he added.