Bermuda-based TyCom, a high-tech unit of the manufacturing conglomerate Tyco International, made its debut on the New York Stock Exchange yesterday and became the largest percentage-gainer for the day and the second most actively traded stock.

TyCom's stock rose as much as 18 percent to $38 yesterday when more than 32 million shares traded hands during their debut on the New York Stock Exchange.

It later settled at 36, up 4 on the day. The company's initial public offering raised nearly $2 billion, meaning that TyCom, the world's biggest maker of undersea fibre optic cable, will not have to borrow money from its parent company, also based in Bermuda with primary operations in Exeter, New Hampshire.

According to CBS.MarketWatch.com, TyCom's was the third largest IPO to hit US exchanges since AT&T Wireless went public in April and generated $11.5 billion.

After TyCom raised twice as much as originally expected from its IPO, Tyco Chairman Dennis Kozlowski said it was no longer necessary for TyCom to use credit lines established by the parent company.

"We're quite pleased with (the IPO),'' Kozlowski told Reuters. "We're long-term holders of the stock.'' Wednesday's robust demand for TyCom's 61.13 million IPO shares drove the price up to $32 per share from the initial band of $20-$25 a share. The company also boosted the number of shares offered three times and raised $1.96 billion.

Kozlowski, whose company holds about an 88 percent stake in TyCom, said the unit's plans were never constrained by cash. TyCom had planned to enter into a credit agreement with Tyco to borrow up to $1.25 billion, according to its filing with the U.S. Securities and Exchange Commission.

TyCom told the SEC its plans to use $1.24 billion from the IPO proceeds to build a network of 70,000 kilometres (43,750 miles) of undersea cable along the floor of the Atlantic Ocean while connecting 30 of the world's major telecommunication centers, including New York, London, Paris, Tokyo and Hong Kong. The cost of the project's first phase is estimated at $5.7 billion.

TyCom IPO TyCom also plans to pay a $200 million dividend from its IPO proceeds to TGN Holdings Ltd., a wholly owned subsidiary of Tyco, according to SEC filings.

For the six months ended March 31, TyCom earned $135 million on revenue of about $1.3 billion.

Kozlowski said TyCom holds about 45 percent of a $12 billion market for making and maintaining cable that stretches along the floor of oceans.

"We will be in the water with our Atlantic system a year from now,'' he said.

He said the fibre-optic cable industry is one in which demand increases as prices fall.

"It's becoming less expensive. For every one percent decrease in price, we're seeing a 2 to 3 percent increase in demand,'' Kozlowski said.