Red chip Stone Electronic Technology lifted net profit in the six months to June 30 more than fourfold to HK$286.1 million from a year earlier.
However, most of the increase for the electronic-appliance maker came from an unrealised gain of HK$362.74 million on equity securities.
Last year, the company did not book any unrealised gain on equity securities.
It is believed the gain was mostly generated by its 8 per cent stake in Nasdaq-listed Chinese Internet portal Sina.com.
Sina.com, China's most visited portal, listed on the Nasdaq on April 13. It rose to a record high of US$54.50 on May 22. But by Tuesday, it had dropped to US$17.125 - up a mere 12.5 US cents from its issue price of US$17.
With turnover of HK$471.96 million, Stone Electronic turned an operating profit of about HK$2.91 million, representing a 0.61 of a per cent gross profit margin.
