Singapore shares closed marginally higher on Wednesday, with several US tech firms losing significant market share, as Asian markets closed mixed ahead of the highly anticipated speech on Friday by US Federal Reserve chair Jerome Powell.

The Straits Times Index (STI), a key benchmark for the Singapore Exchange, ranged between 4,204.41 and 4,232.10 throughout the day. It ended the session at 4,219.54, up 3.35 points or 0.08% compared to Tuesday's close.

In company news, shares of Lum Chang Creations (SGX:LCC) surged nearly 9% at the close as the company projected a significant improvement in its profit before tax for the fiscal year ended June 30.

PC Partner Group's (HKG:1263, SGX:PCT) shares were down nearly 5% in Singapore, as its attributable profit to owners during the first half of the season increased 29% to HK$250.4 million from HK$194.1 million a year earlier.

Meanwhile, Astaka (SGX:42S) was down over 5% following the launch of a mixed-use development worth around 1.2 billion ringgit in Johor, Malaysia.