In a novel laboratory asset market, traders buy and sell shares of a monopolist while observing its price and transaction history in real-time. Dividends are based on the profitability of the monopolist, also an experimental subject. Despite dividend uncertainty resulting from both monopolist behavior and imperfect information about product market fundamentals, the present value of the dividend stream provides the best estimate of observed asset prices. We compare our data to previous experimental asset markets in which dividends were drawn from a known discrete distribution. While we still detect some mispricing, asset price bubbles are significantly smaller when dividends depend on an observable market process.