Hong Kong’s stock exchange has issued new rules that bar companies whose assets are mostly or entirely cash from listing, effectively banning a common method of backdoor listing in the territory, South China Morning Post reported, citing a statement from chief regulatory officer David Graham. The bourse’s chief regulatory officer and head of listing, David Graham, said that the new guidance was needed in light of a surge in listed companies proposing large-scale fundraising rounds, which can lead to cash injections that allow the investors who buy the shares to take control of the issuers and invest the money into new businesses.