Practices of fraudulent stock trading are still rampant although local regulators pledged to reinforce their scrutiny of alleged perpetrators of financial crimes.

Apart from manipulators — who issue bogus trading orders for price-rigging — other major scammers continuously tainting the equity market are those who make irregular gains by using insider corporate information.

Data from the Korea Exchange showed that the number of unfair stock trading allegations came to 64, in the first half of 2015. This is a 10.3 percent increase over the corresponding period last year.

Among the collective unfair trading, the irregular use of insider information took up 34.3 percent, or 22 cases, during the January-June period this year.

A recent case relates to Hanmi Pharm stocks. The company has been drawing close attention among investors as one of the best-performing company, along with its parent holding firm Hanmi Science, on the main bourse so far this year.

The firm saw its stock price zoom up 730.3 percent in less than a year to 847,000 won ($716.80) on Nov. 23 from 102,000 won in the last trading session of 2014. It closed at 660,000 won last Friday.

Its noteworthy gain was ascribable to trillion-won drug development deals with two global firms in France and the U.S., respectively. It marked the first time that a Korean pharmaceutical firm signed an international contract on developing a new medication.

The firm, however, failed to block a loophole in its internal control. Last week, a staff researcher at Hanmi Pharm was indicted for taking irregular investment gains by passing over insider information to a stock analyst, who also faced court trials.

More seriousness lies in the allegation that the stock analyst again leaked the info to some institutional and small investors. The financial authority and prosecution allege that the combined irregular gains, reaped by the directly or indirectly implicated, exceeded 20 billion won.

In a similar vein, a group of scammers including several certified public accountants were indicted last month for making unfair gains with undisclosed information of their corporate client.

Buying stocks using insider information before the company announces a major news is similar to that of a student taking an examination after stealing the test questions in advance.

Even though the stock trading with insider information may have little impact on equity prices in terms of rigging, it is a critical breach of code of conducts, which hampers transparency in the capital market and undermines investor sentiment.

Regulators, including the Financial Services Commission and Financial Supervisory Service, need to carry out full-fledged efforts to retrieve this sort of improper gains and levy tough fines and propose criminal sanctions on the violators in close collaboration with law enforcement agencies.

In the U.S., the Securities and Exchange Commission publicizes the names of individuals and institutional investors engaged in stock scams. The stern regulatory policy is similar in the U.K. and Japan.

Management of publicly traded companies should also bolster their internal control and turn up the heat on staffers’ moral hazard, if any.

If the sanctions against capital market perpetrators stay at a negligible level and are relatively lenient compared to punishment in other sectors, the government’s commitment to fostering an advanced financial market could end up in empty talk.