Linklaters and Clifford Chance had the lead roles on Bank of China Ltd.’s $6.5 billion share sale in Hong Kong.

China’s fourth-largest state-owned bank sold tier 1 preference shares in order to meet stricter Basel III global bank capital adequacy rules, which came into force last year. The preference shares act in ways like a convertible bond, paying a coupon of 6.75 percent and having the potential to convert to Bank of China common stock if its reserve capital falls below certain levels.