For three years, from 2001 to 2003, the market capitalisation of highly boarded companies (HBCs – which have directors who are on multiple boards) ranged between 33 to 43 percent, it peaked at 70 percent in 2007, and was at 66 percent in 2010, according to the study. When the listed companies were mandated by the government to have a higher percentage of non-aligned or independent directors on the boards, the expectation was that there would be a widening of pool of independent directors. But, the researchers have found, the mandate has tended to increase multiple directorships and concentration of economic power, because in many cases, such additional independent director vacancies have been filled by incumbent directors from other companies. The population of highly boarded directors has increased from 40 in 2001 to 71 in 2010. The total number of directors of NSE-100 companies is 1,104, while 284 companies are HBCs. The highly boarded directors constitute about 6 per cent of the overall director population of NSE-100 companies, the study says. These trends suggest that despite the well-intentioned regulatory reforms, the extent of over-boarding among directors has not come down, there is actually a marginal increase, the researchers have concluded.