Clearwire Corp. announced it has received a proposal by satellite-TV provider DISH Network Corp. (BB-/Positive/--) to purchase about 24% of Clearwire's spectrum for $2.2 billion. DISH will also try to acquire at least a quarter of Clearwire's common stock for $3.30 per share with certain governance rights. Ratings for Clearwire and majority-owner Sprint Nextel Corp. remain on CreditWatch with positive implications. On Jan. 10, 2013, Standard&Poor's Ratings Services said that the 'B+' corporate credit rating, and all other ratings, on Overland Park, Kan.-based wireless carrier Sprint Nextel Corp. remain on CreditWatch with positive implications. The ratings were placed on CreditWatch on Oct. 11, 2012. Additionally, our 'CCC' corporate credit rating, and all other ratings, on Bellevue, Wash.-based wireless