Moody’s Investors Service has raised its outlook on Clearwire Corp to stable from negative after the wireless service provider entered an agreement with its largest customer and majority shareholder Sprint Nextel Corp, Economic Times reported.

The credit rating company affirmed Clearwire’s Caa2 corporate family rating, eight levels below investment grade, as Moody’s said the relationship between Clearwire and Sprint is beginning to heal.

According to Moody’s, improving the relationship between the two companies, if sustained, could foreshadow an improvement in Clearwire’s operational and financial profile. Moody’s said Clearwire’s ratings could be raised if the company is able to secure the necessary funding to deploy a nationwide fourth-generation network, however, its ratings could be lowered if it is not able to secure the funding.

Thursday, Clearwire entered into a 4 year contract with Sprint Nextel Corp worth $1.6 billion. Sprint will be paying $926 million for unlimited use of Clearwire’s WiMax 4G network through 2013, giving Clearwire a needed cash infusion. Moody’s Investor Service is a source for credit ratings, research and risk analysis.

Apart from its core ratings business, Moody’s provides research data and analytic tools for assessing credit risk and publishing market-leading credit opinions, deal research and commentary. It serves more than 9,300 customers accounts at some 2,400 institutions around the globe.