Shares of a Beijing airport operator are prepared for a 45% takeoff, according to an American investment bank. But for prospective investors, visibility is close to zero.

Beijing Capital International Airport Company (ticker: 694.HK) owns and manages a single asset: its namesake airport, which is the world’s second-busiest behind Hartsfield-Jackson Atlanta. The company is controlled by a state-owned enterprise, and airline and passenger fees are tightly regulated. Upside comes from growing less-regulated concessions, such...