Buyout firm Permira has given investors in its latest fund the option to put a limit on commitments when the vehicle becomes 60% invested, in exchange for lower future profits, as private equity firms grow increasingly worried investors will default on their allocations to the asset class.

Permira has contacted the 180 investors in its fourth fund allowing them to stop commitments when the fund becomes 60% allocated. It already has 52% of its capital deployed.