Sprint posted its fourth quarter earnings report for 2013 this morning, with highlights including the highest number of subscribers ever for the company. The third-place carrier reports a loss of $1 billion, which is less than the $1.3 billion it lost in the same quarter a year ago. Sprint now has 53.9 million subscribers, its highest number ever, after adding 58,000 post paid subscribers, 322,000 prepaid subscribers, and 302,000 wholesale subscribers last quarter.

For network news, Sprint now claims to cover 200 million people with LTE and has its Sprint Spark service in 14 markets. Sprint's LTE network is still far behind competitors such as AT&T, Verizon, and even fourth-place carrier T-Mobile, though it expects to cover 250 million people by the middle of this year. The carrier says it will have its high-speed Spark service in 100 cities within the next three years.

Sprint says it sold 5.6 million smartphones in Q4, but doesn't break down how many were for each platform. For the year, the carrier sold 20.5 million smartphones. Ninety-five percent of Sprint's postpaid customers purchased smartphones, compared to 93 percent at AT&T and 88.9 percent at Verizon.

Despite its growth, Sprint's struggles continue, and it's the only major carrier that's reported its Q4 earnings in the US to not turn a profit this quarter (T-Mobile will issue its Q4 report later this month). Rumors that Sprint's new parent company, SoftBank, has been very interested in purchasing T-Mobile have been circulating for months, though opposition from regulators may put a damper on any moves there. With SoftBank at its side, Sprint has plenty of cash and support to weather losses, it just remains to be seen how long SoftBank will continue to put up with them.

Update: During a conference call discussing the company's earnings, Sprint CEO Dan Hesse said that he was in support of further consolidation within the wireless industry, so long as it doesn't involve AT&T and Verizon. "I've said consistently for some time that I believe that further consolidation in the US wireless industry — outside of the big two, outside of AT&T and Verizon because they're so large — would be good for the dynamic, good for the country, and good for consumers," Hesse said.

With regards to Sprint's rumored interest in T-Mobile, Hesse's language suggests that Sprint isn't opposed to a purchase and would argue that it would be favorable for the industry. Beyond that, he declined to comment. "I think I read in the newspapers that we were going to announce a transaction today," Hesse joked. "Seriously, I don't comment on media speculation."