Didi Global Inc. plunged in U.S. trading as the ride-hailing company faced scrutiny over its data security and a broader Chinese crackdown on companies listing their shares abroad.

China’s State Council issued a sweeping warning to China’s biggest companies, vowing to tighten oversight of data security and overseas listings. That announcement followed the opening of a security review by China’s internet regulator last week and a demand for app stores to remove Didi.

Didi’s American depositary shares fell 20% to $12.49, wiping out about $15 billion of market value and taking the stock below the $14 price from its initial public offering. Beijing-based Didi controls almost the entire ride-hailing market in China and raised $4.4 billion last week in the second-largest U.S. IPO for a Chinese firm.

The State Council’s broadside marked an escalation in President Xi Jinping’s campaign to bring the nation’s technology firms — and their reams of valuable data — under control. Over the weekend, China also moved against two other companies that also recently listed in New York, — Full Truck Alliance Co. and Kanzhun Ltd., Ltd. The warning “is aimed at securities violations, but it also makes special provisions for cross-border data supervision, which signals that data supervision has become one of the most important regulatory fields in China,” said Xia Hailong, a lawyer at the Shanghai-based Shenlun law firm.

“Sine there is no mechanism in place for cross-border supervision of securities, conducting a security review on data could serve as an effective tool for Chinese regulators to rein in overseas listed companies,” he said. Source: Bloomberg