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By Sinead Carew
NEW YORK, July 11 (Reuters) - Sprint Corp on Thursdayoffered unlimited data services for the lifetime of an account,as the No. 3 U.S. wireless operator looks to lure customers awayfrom bigger rivals Verizon Wireless and AT&T Inc.
The announcement came just a day after SoftBank Corp closed its $21.6 billion purchase of 78 percent ofSprint and two days after Sprint closed its buyout of ClearwireCorp, which has a vast amount of wireless airwaves licenses.
Sprint already offers unlimited data services for a flatmonthly fee, but because of network capacity concerns analystshave long questioned whether it would eventually be forced tofollow its rivals who charge consumers depending on the amountof data they use.
Sprint Chief Executive Dan Hesse told Reuters the newguarantee would reassure customers worried about leaving AT&T orVerizon Wireless for Sprint only to have the offer of unlimitedservices pulled at some point.
"Our research has shown that is a big issue for us inattracting AT&T and Verizon customers," he said, adding that theguarantee "clearly differentiates" Sprint from its rivals.
Hesse, who has been battling customer losses at Sprint sincehe took on the top job in December 2007, said he had to completethe Clearwire deal so Sprint could have "the capacity to be ableto offer an unlimited guarantee for life."
Without Clearwire's airwaves, Hesse said Sprint "would haverun out of gas" on capacity in a few years.
Sprint, which is years behind its big competitors inupgrading to high-speed data services, is working on amulti-billion dollar network to close the gap. It will use cashfrom SoftBank and Clearwire airwaves to support the effort.
But while Sprint's ability to offer unlimited services at aflat fee gives it a marketing advantage, BTIG analyst WaltPiecyk thinks its success in luring customers away from rivalswill depend mostly on how quickly it can beef up its network.
"They need to change the perception of their network,"Piecyk said.
SoftBank has said its top priority at Sprint will be toimprove the network as quickly as possible.
Analysts expect the SoftBank and Clearwire deal to amp upcompetition in the U.S. wireless market because Japan'sSoftBank, run by billionaire Masayoshi Son, is famous foraggressive pricing in its home market.
Son, who will be the Chairman at Sprint, also won a bitterbattle with Dish Network Corp Chairman Charlie Ergen tobuy both Sprint and Clearwire.
"The excitement for investors and consumers is that Sprintnow has the spectrum assets, the money to build its network anda leader that has the courage to do it," Piecyk said. "Whetherthey can execute on that remains to be seen."
Along with AT&T and Verizon Wireless, a venture of VerizonCommunications and Vodafone Group Plc, Sprintalso has to contend with tough smaller rival T-Mobile US Inc, the No. 4 U.S. mobile service provider.
On the day that Sprint closed its SoftBank deal, T-MobileCEO John Legere announced his company would allow customers toupgrade their phones every six months, which is four times moreoften than its competitors.
Hesse declined to comment on any other changes Sprint andSoftBank will put in place now that the deals are closed.
Sprint also made some small pricing tweaks on Thursday tosimplify family plans and service plans for individualsmartphone users.
Under its latest offerings, smartphone users will pay $240less per year than the customers of market leader VerizonWireless and $120 less per year than No. 2 U.S. operator AT&Tand T-Mobile US.
The shares of Sprint, which changed its name from SprintNextel to Sprint Corp after the deal, will trade on a "whenissued" basis until Friday when it will begin trading againunder the S ticker symbol.
