The US SEC has issued warning letters effectively blocking the launch of several high-octane ETFs designed to deliver three and five times the daily returns of stocks and cryptos. The regulator is concerned that these leveraged funds—which sought to exceed the current 2x leverage limit—have risk exposures that may violate SEC limits relative to their assets.

The end of the government shutdown left the SEC with an avalanche of paperwork, forcing staff to prioritize new company registration statements critical for initial public offerings (IPOs). More than a dozen companies had to revise their IPO timelines due to the delays, creating market uncertainty.

The US Securities and Exchange Commission’s examiners will step up scrutiny of financial firms’ use of artificial intelligence next year, the latest sign of regulators’ growing concerns about the emerging technologies.