Motorola ( MOT) recently announced the sale of most of its wireless networking equipment businesses to Nokia ( NOK) for $1.2 billion in cash. This transaction is expected to close by the end of 2010. We think this was a smart move by Motorola. The company's wireless network equipment sales declined from $6.2 billion in 2005 to $4.1 billion in 2009, and seemed unlikely to recover. The sale leaves Motorola with a stockpile of cash it can invest in its core mobile phone business, where it faces fierce competition from Apple ( AAPL), Nokia and others. Our analysis follows below. Prior to this transaction, we believed that Motorola's mobile phone market share would continue to decline, from 4.45% in 2009 to 1.50% by the end of the Trefis forecast period. However, the Nokia transaction gives Motorola $1.2 billion to invest in mobile phone R&D and sales support (selling, general and administrative expenses) next year and boost the company's total spend on indirect expenses to $5.7 billion. Based on Motorola's success in launching innovative, popular smartphones like the Droid over the past two years, we believe that this additional investment could potentially boost the company's mobile phone market share to 3.5% in 2011, instead of the 2.2% that we forecast. This scenario could yield an upside of 20% to the $7.42 Trefis price estimate for Motorola's stock .