SINGAPORE - StarHub chief executive Tan Tong Hai bought more than half a million dollars' worth of the company's shares on the open market on Thursday (Feb 15) as the stock fell to a six-month low.

Shares in the telco reached a low of $2.56 on Thursday, a 10.14 per cent plunge and the largest one-day decline since StarHub's IPO in 2004. The last time the stock was this low was around mid-August last year.

In a Singapore Exchange filing on Monday, the group said Mr Tan purchased some 200,000 shares at $2.59 apiece last week. This represents a 10.4 per cent discount to StarHub's closing price of $2.86 per share on Feb 14, the last full market day before the transaction.

Following the deal, Mr Tan's shareholding in the company will increase to 754,854 shares, or 0.04 per cent from 0.03 per cent previously.

Mr Tan is due to step down from his position as CEO, and relinquish his appointment as StarHub's executive director with effect from May 1.

Shares in the telco last traded at $2.57 on Thursday, down 10 per cent, or 29 cents.