CIBC World Markets is shuffling responsibilities among its existing loan group following the Jan. 11 resignation of corporate lending co-headFrank Brittan.Richard Hassard, co-head of CIBC's credit capital markets arm and Brittan's ex-boss, confirmed Brittan's resignation and said it was for personal reasons, stressing that Brittan was not let go by the firm. Hassard noted that a decision on whether to replace Brittan has not been made. Brittan was responsible for lending within the capital market division. As of last week he had not joined another firm.