Shares of Chinese streaming company iQiyi Inc. are up 14% in Thursday trading, putting the stock on pace for the best single-day percentage gain in its history. Shares have posted five double-digit percentage gains since the beginning of May. IQiyi, which was split from Baidu Corp. in March, made a number of announcements Thursday, including that it was adding Jane Sun, the Chief Executive Officer of Ctrip.com International Ltd. as an independent director of its board. The company also said it was starting an artificial-intelligence competition centered on "video-based multimodal biometric recognition." The stock is now trading at more than double its March IPO price of $18. Shares are up 51% so far this month, while the S&P 500 has gained 4.1%.