By Tatiana Bautzer, Guillermo Parra-Bernal and Liana B. Baker SAO PAULO/SAN FRANCISCO (Reuters) - Online travel agency Decolar.com Inc, one of Latin America's few so-called unicorns, has held preliminary talks with investment banks for a U.S. listing on Nasdaq in the second half of 2017, three people with knowledge of the plan said. New York-based investment firm Tiger Global Management LLC, which owns 60 percent of Decolar.com, is spearheading the plan on the understanding that the 17-year-old Argentine company is sufficiently established and well-recognized to go public, said the sources, who requested anonymity since the plan is private. According to two of the sources, Decolar.com has yet to hire the banks to underwrite the listing, although talks with some of them have taken place. The second source said Citigroup Inc , Morgan Stanley & Co , JPMorgan Chase & Co and an unnamed Brazilian peer are candidates for underwriting roles. A media relations executive working for Decolar.com confirmed the initial public offering plan without giving additional information. Tiger Global Management's media office declined to comment, as did the banks. Decolar.com is a "unicorn," as private technology companies valued at more than $1 billion are known. Many Latin American startups, some of them unicorns too, collapsed when the U.S. technology bubble of the early 2000s burst. Online travel agents around the world have gained business scale over the past decade by taking advantage of their digital platforms to draw customers from traditional hotel- and flight-booking companies. In Argentina, where Decolar.com is based, vibrant investments in technology firms are seen as a way to turn around an economy too reliant on commodities. Entrepreneur Roberto Souviron founded Decolar.com in 1999. It operates in nearly two dozen Latin American countries through the Spanish-language website Despegar.com and the Portuguese-language site Decolar.com. The company had $3.5 billion in gross bookings last year, of which about 40 percent came from Brazil, two of the sources said. The metric was about 10 times that of CVC Brasil Operadora e Agencia de Viagens SA , Brazil's largest listed travel agency. Tiger is one of the largest investors in Brazilian startups, owning stakes in companies such as fintech Nubank Brasil SA and e-commerce venture N2com Internet SA, known by the shoe retailing brand Netshoes. Other Decolar.com shareholders include Expedia Inc and investment firms General Atlantic LLC, Sequoia Capital LLP, Insight Venture Partners LLC and Accel Partners Management LLP. According to the sources, Decolar.com was valued last year at $1.4 billion when Expedia bought a stake of about 20 percent for $270 million. (Editing by Lisa Von Ahn and Lisa Shumaker)