BEIJING — China saw a significant drop in misconduct cases of “rat trading” as the securities watchdog stepped up efforts to crack down on market violations.

Cases of rat trading, known as front-running in US and European markets, slumped 50 percent year-on-year in the first half of 2018, data from the China Securities Regulatory Commission (CSRC) showed. The decline followed a losing streak since last year.

A CSRC official said the illegal practice has been effectively curbed in publicly-offered funds, brokerage companies, and asset management arms of insurance companies.

In a rat trading case, fund managers buy stocks via their own accounts before the financial institutions they work for make large deals and then sell the stocks to make personal gains after the prices rally.

Such violations used to be rampant until regulators stepped in to restore market order, and CSRC probes have resulted in a number of criminal convictions since 2017.

However, the CSRC warned that a rising trend in institutions, including private funds, were disguising their misconduct, vowing to maintain a hardline stance to protect the interests of stock investors.