By Michael Teich

Uber's board leadership is under question as it gears up for its monster IPO.

CtW Investment Group is putting a target on Uber's Audit Committee Chair John Thain, insisting the ride-hailing company owes it to investors to remove him from the board. CtW's research director, Richard Clayton, points to Thain's professional past at Merrill Lynch as a reason for being unfit for his position at Uber.

"He made terrible decisions that not only led to huge losses, but considerable controversy including paying $4 billion in bonuses to Merrill Lynch in at the same time the company was losing $15 billion in one quarter," he said.

CtW works with pension funds sponsored by unions affiliated with Change to Win, a federation of unions representing nearly five million members. While the group says it currently has no financial interest in Uber, Clayton says the firm wants to protect its pension funds from future investment risk.

"We don't currently have any investment in Uber. Our funds, as far as I'm aware, don't have any investments in Uber," Clayton said.

"We have to anticipate that particularly once it starts joining index that our pension funds will end up being shareholders in Uber."

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