HONG KONG: Three years ago, the Stock Exchange of Hong Kong lost the chance to host the record $25 billion initial public offering of Alibaba Group Holding because regulators would not allow the company’s founders certain privileges they regarded as contrary to the principle that all shares carry equal voting rights. If Hong Kong is to become competitive in attracting listings by high-tech and disruptive companies amid a general slowdown in IPOs on the exchange, a more flexible approach is called for.