Chicago-based clearing house OCC has appointed two new board members.

Banking executive Susan Lester has joined the firm as a public director, replacing Matthew Gelber of Bitterroot Asset Management.

Meanwhile William Yates of TD Ameritrade will take over the member director duties of Judith Kula of Wolverine Execution Services.

Both have been elected to three-year terms.

“The additions strengthen our ability to ensure confidence in the financial markets and the broader economy as a systemically important financial market utility,” OCC's chairman Craig Donohue said in a statement.

The group, which recently had a controversial capital plan approved by the US Securities and Exchange Commission, is the only central counterparty in the US that clears stock loan trades.

OCC has also decided to re-elect Raymond Di Sanza of Charles Schwab and Jonathan Werts of Bank of America Merrill Lynch as member directors.

Kepos Capital’s Robert Litterman will stay on as a public director.