突然，“入通”股频频巨震，发生了什么？

Core Viewpoint - The recent inclusion of several Hong Kong stocks into the Stock Connect program has led to significant price volatility and increased trading volumes, presenting both investment opportunities and risks [2][12]. Group 1: Stock Performance Post Inclusion - Multiple stocks, such as Yaojie Ankang-B and Baize Medical, experienced dramatic price increases after being included in the Stock Connect, with Yaojie Ankang-B rising by 20.13% on the inclusion date and peaking at over 10 times its initial price shortly thereafter [4][5]. - However, these stocks also faced severe corrections, with Yaojie Ankang-B dropping by 53.73% on September 16 and further declines following [4][5]. - Other stocks like Brain Dynamics-B and Baize Medical also showed similar patterns of extreme volatility and trading volume spikes post-inclusion [5][12]. Group 2: Reasons for Increased Volatility - The volatility is attributed to several factors, including adjustments in index constituents that led to passive buying by ETFs tracking these indices [8][9]. - The inclusion of these stocks allowed mainland investors to participate, bringing in additional capital and increasing buying pressure [10]. - Speculative trading, particularly in innovative pharmaceutical stocks, has also contributed to the price swings, as these stocks are perceived to have high growth potential [11][13]. Group 3: Trading Volume Surge - Following their inclusion, stocks like Yaojie Ankang-B and Baize Medical saw their average daily trading volumes increase significantly, sometimes by several times or even dozens of times compared to pre-inclusion levels [5][12]. - The influx of capital and heightened trading activity has made these stocks more susceptible to rapid price changes [13].