Director appointment restrictions: cooling-off periods required before non-independent or public interest directors join another depository or exchange. Amendment to regulation 25 mandates that non-independent directors and public interest directors may be appointed to another depository, recognized stock exchange, or recognized clearing corporation only with the Board's prior approval and after a cooling-off period as specified by the appointing depository's governing board; the cooling-off requirement for public interest directors applies only when appointment is to a competing depository.