NEW YORK (Bloomberg) ? Mexican billionaire Carlos Slim sold more than 12 percent of his stake in Global Crossing Ltd., taking advantage of a two-week surge in shares of the fibre-optic network operator.

Slim, the second-largest shareholder in Bermuda-based Global Crossing, sold 539,758 common shares now valued at about $14.4 million on March 23 and 24, according to a filing yesterday with the US Securities and Exchange Commission. He sold the stock at between $23.50 and $25.43, trimming his stake in the company to 17 percent from 19 percent.

?People are getting excited about the backbone providers,? said Greg Mesniaeff, an analyst at Needham & Co., referring to companies such as Global Crossing that have national networks. ?There is a growing perception of scarcity value there.?

Shares of Global Crossing, which emerged from bankruptcy in December 2003, have jumped 47 percent since March 16, when chief executive officer John Legere said customers such as Microsoft Corp. and the UK?s Vodafone Group Plc were buying more network capacity.

Shares of Global Crossing and rivals including Level 3 Communications Inc. are gaining amid investor optimism that traffic on their networks will increase, driven by increased use of the Internet to move music, movies and telephone calls.

Slim, 66, first reported buying a Global Crossing stake in March 2004, after the shares plunged 38 percent in a single day following the company?s forecast of a wider loss amid declining sales.

Family investment vehicles such as Immobiliaria Carso SA said on March 19 of that year that they bought stock at between $16.13 to $20.64. They said in July that they bought more shares for as little as $12.60.

Andres Ortiz, a spokesman for Slim, declined to comment. Becky Yeamans, a spokeswoman at Global Crossing?s US offices in Florham Park, New Jersey, also declined to comment.

Yesterday?s sales represent the first time that Immobiliaria Carso has reported a reduction in its Global Crossing stake.

Global Crossing shares rose 67 cents to $26.62 as of 3:20 p.m. in Nasdaq Stock Market composite trading.

Level 3 Communications, which yesterday raised its first-quarter profit forecast, rose 8 percent, bringing its two-day gain to 25 percent.