The companies say they are exploring separating those businesses entirely. That could mean a stock offering is in the works.
Microsoft will make a $300 million investment in the subsidiary for an approximately 17.6 percent stake. Barnes & Noble will own about 82.4 percent of the subsidiary, which has yet to be named.
The companies say the subsidiary will help to speed the transition to e-reading. Barnes & Noble sells the Nook e-reader. The Nook app will make Barnes & Noble's catalog of e-books, magazines and newspapers available to Windows customers.
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