In late April, U.S. Securities and Exchange Commission chair Jay Clayton and William Duhnke, chair of the Public Company Accounting Oversight Board, issued a joint statement warning investors of the risks of investing in companies from emerging markets. Although the document wasn’t specific, it’s clear that the duo are really concerned about one particular emerging market: China.

The day after releasing the statement, Clayton, who before being appointed by President Donald Trump to run the SEC was a longtime Sullivan & Cromwell partner and advised on the largest-ever U.S. initial public offering from China, Alibaba’s 2014 listing, went on Fox Business to reiterate the warning, stressing in particular that the oversight board’s inability to monitor Chinese companies’ books compounds the risk.