Inside a Sprint Corp. Location Ahead Of Earnings Figures
Customers shop at a Sprint Corp. store inside the James R. Thompson Center in Chicago, Illinois on July 22, 2016.  Christopher Dilts — Bloomberg via Getty Images

Here’s How Much Sprint Wants to Raise by Mortgaging Its Airwaves

Updated: Oct 12, 2016 8:07 PM UTC

Sprint, the No. 4 U.S. wireless carrier, said on Wednesday it planned to raise an initial $3.5 billion by mortgaging about 14% of its wireless airwaves.

The company, majority owned by Japan's SoftBank, estimates the airwaves are worth about $16.4 billion.

The spectrum portfolio, which includes FCC licenses and a small number of third-party leased license agreements, would be leased back, the company said.

The offering is expected to be rated investment grade by Moody's Investors Service and Fitch, Sprint said.

The carrier has been burning through cash as it faces intense competition for subscribers. The company had negative cash flow of $3.17 billion in the financial year ended March 31.

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Sprint (s) raised $1.2 billion in November and $2.2 billion in April through similar sale and lease-back deals.

The Wall Street Journal first reported Sprint's plan on Tuesday.