The chase for yield saw strong demand for Hyflux's perpetual securities, which prompted the water treatment company to expand its offering from $300 million to $500 million yesterday.

The company's $50 million placement tranche to institutional investors was oversubscribed by four times after the offer closed at 6pm.

Likewise, its public offering of $115 million was oversubscribed by more than three times, with $368 million of valid applications, as retail investors chased the 6 per cent annual returns promised.

In total, about $329 million was taken up by the public, $165 million by institutional investors and about $6 million was allocated to directors, management and employees of Hyflux and its subsidiaries.

Hyflux executive chairman and chief executive Olivia Lum said the response was an enthusiastic one, showing belief in the company's growth strategy.

Perpetual securities, unlike bonds, do not have a fixed redemption date. Companies may also defer the payments of the distributions indefinitely, and investors have no recourse if such a deferral is made.

Still the strong demand showed that the hunt for returns is still on, with observers noting that the 6 per cent yield is an attractive one.

"Private banks took up a big chunk of the tranche. Clients still want yield," said a private banker who declined to be named.

The payments are semi-annual, with the first distribution expected in November.