Following the sale of McCaw Cellular, McCaw took interest in Nextel, a then-floundering wireless carrier. By April 1995 McCaw gained effective control of the company contributing, along with his brothers, $1.1 billion over time. Within four years Nextel grew significantly to become a challenging wireless competitor, servicing 3.6 million customers throughout the U.S. and ten of the largest international markets. In 1999 McCaw formed Nextel Partners, Inc. which was later acquired by Sprint Nextel, Inc., for $6.5 billion in 2006, following a $36 billion merger between Nextel and the Sprint Corporation in 2005.