Here are the 2 main drivers to SGX's September profit growth

Greater derivative volume, higher clearing fee.

According to OSK-DMG, while average daily turnover (ADT) in the securities market was broadly stable at SGD1.3bn, securities revenue rose 15% y-o-y.

"Average clearing fee increased to 3.2bps from 2.7bps a year ago, as the proportion of capped trades fell to 35% from 46% in 1QFY13, with institutions trading a broader range of stocks and retail participation rising," said the research firm.

"Turnover velocity, however, was weaker at 47% (1QFY13: 51%; 4QFY13: 55%). Meanwhile, derivatives revenue was up 16% y-o-y as total traded volume jumped 36% y-o-y to 26.4m contracts, led by the FTSE China A50 futures, Nikkei 225 futures and options, and iron ore swaps. Q-o-q, revenue fell 9% reflecting weaker ADT (-16% q-o-q) and derivative volume (-16% q-o-q)," it added.

Aside from these two drivers, the fact that SGX was able to keep expenses broadly under control -- growing only 6% y-o-y and actually dipped 6% m-om -- contributed to a rosier bottom line.

Management continued to guide for FY14 operating expenses of SGD320m-330m (FY13: SGD300m). Technology-related capital expenditure is expected be around SGD35m-40m.