Facing pressure from investors and heightened scrutiny from federal regulators, some of the largest private equity firms are giving up their claim to fees that generated hundreds of millions of dollars for them over the years.

The investment firms usually collect the fees from companies they buy for providing services such as consulting, serving as directors and helping them make their own acquisitions. Instead of keeping some of the money, the buyout firms, in new funds they are raising, will now pass the fees on in full to investors in the funds.