Beijing: For weeks now, optimists have said China's tech crackdown has been priced in by the stock market. A fresh round of regulatory angst has shaken that thesis to its core. The market capitalization of shares in a gauge of China's internet sector dropped by about $200 billion this week alone, as Beijing vowed to increase scrutiny over data collection and overseas listings. It has slumped by more than $1.1 trillion since a Feb. 17 peak, with the index down some 35%, according to calculations by Bloomberg. China's pivot to data-amassing titans such as Didi Global Inc. has created a fresh round of uncertainty for investors already dealing with scrutiny in areas such as fintech, anti-monopolistic practices and after-school tutoring. Besides Big Tech, stocks linked to live marketing, electric-vehicle production and the education industry also look vulnerable.