Thailand’s telecommunications companies have the dubious honor of leading the global industry in share declines over the past three months.

True Corp. Pcl and Advanced Info Service Pcl were the biggest losers among the more than 80 companies in the Bloomberg World Telecommunications Index the past three months. Both True and Advanced fell about 40 percent in the period. The results were even worse for rival operators Total Access Communication Pcl and Jasmine International Pcl, Bloomberg data show.

Shares of phone companies have slumped after auctions of four new licenses in November and December. The winning bids of a combined 233 billion baht ($6.4 billion) were more than quadruple the starting prices, and the top offer in the latter sale by Jasmine, which previously focused on Internet services, adds a new competitor to the mobile-phone industry. The license sales were designed to make so-called 4G services available across Thailand.

“I am now more negative on Thai telecom following the second auction,” said Yeu Huan Lai, Singapore-based senior fund manager at Nikko Asset Management Ltd. “More than the impact of the high auction price, I’m concerned with the entry of a new competitor.”

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