Zune blog ClicZune cites reports from Zunerama and ZuneThoughts that suggest a substantial number of songs purchased from the Zune Marketplace simply can't be shared at all. Both reports have found that the Zune refuses to share around 40% (±2%) of songs from major artists. Worse, many of the prohibited songs are licensed from Universal, the very same label that struck a deal with Microsoft in order to get royalties on each Zune sold. Artists with prohibited songs include Blue October, Eminem, Gwen Stefani, Snow Patrol, Jay-Z, and JoJo. Thanks to Engadget for the tip.