[Edit: math was corrected above] I'm not following your math, 18.2 million shares of Apple today would be worth about $9.8 billion--for a $151 million investment. I'm sure there are nuances that I don't fully grasp; but that's a huge discrepancy.

FWIW, I didn't mean to imply that MS should have held onto that investment; I was only answering the question about the purely financial ROI.