Former officials from the judiciary and finance-related branches of the government appear to be popular recruits for conglomerates across the country, as industry data showed Tuesday that over 20 percent of former civil servants working as directors at companies used to be prosecutors.

Of the 11,208 directors at the 30 biggest conglomerates in South Korea by assets, 337 of them -- or 3 percent -- were ex-civil servants, according to a corporate analysis firm Leaders Index. Of these, 75 were former prosecutors, which accounts for 22.3 percent of government officials-turned-corporate executives.

The report researched data on a total of 298 affiliated companies of the 30 conglomerates.

The majority of the ex-prosecutor employees at companies were non-executive directors, which refers to those who are board members but not employees or stakeholders in the companies. The only former prosecutor to hold an executive position was Cho Jeok-yeong, a former director prosecutor of the Seoul District Prosecutors' Office who joined Kakao to oversee compliance management at the company.

The report showed that after prosecutors, former judges were most likely to get high-ranking posts at companies. A total of 53 former judges were directors at conglomerates -- 39 of them non-executive directors.

A breakdown by government organization shows 38 former employees of the National Tax Service were company directors, followed by 26 former officials of Financial Services Commission or Financial Supervisory Service, 23 who used to work at the Ministry of Trade, Industry and Energy, 21 former officials of the Ministry of Economy and Finance, 16 who used to work at the presidential office, and 12 formerly employed by the Korea Fair Trade Commission.

In terms of which conglomerate had the highest percentage of former government officials among its directors, Shinsegae Group led all companies with 11.4 percent -- 18 out of 158 -- followed by Nonghyup's 9.4 percent and Hanjin Group's 8.8 percent.

LG Group had the lowest percentage, as only four of its 940 directors -- 0.4 percent -- used to work for the government.

Number-wise, Samsung Group had the highest number of ex-civil servants among its directors. Forty-nine out of its 2,084 directors formerly worked for the government, which amounts to 2.4 percent.