Making a Facebook clone is about the last reason I can think of for buying Facebook's source. I'm guessing any buyer interested would be looking to use it to find exploits for snooping or worse.
"Making a Facebook clone is about the last reason I can think of for buying Facebook's source." Probably not the first reason, but IMHO it's not that far fetched. The German Facebook clone has has allegedly used parts of Facebooks (client side) source. They have been sued and settled out of court if I remember correctly. (http://en.wikipedia.org/wiki/Facebook,_Inc._v._StudiVZ_Ltd.)
