Facebook shares rose about nine percent in value in the last auction on SharesPost, to close at $33 apiece on Friday, compared to a previous $30.

If the company still had 2.5 billion outstanding shares like we’d assumed, that would put Facebook’s valuation at $82.5 billion. However, SharesPost says lists an implied value of $77.7 billion which means either the private marketplace miscalculated or the number of outstanding shares is just over 2.35 billion.

Quite possibly the entirely unconfirmed rumors of an initial public offering explain for the nine percent rise in the price, but so would the change in the number of outstanding shares. However, we don’t know whether that figure changed between the time of the last two auctions or prior to that.

Regardless, this latest round of trading brings the value of Facebook closer to its record high of $87.5 billion, which the shares haven’t had since early July of this year.

More on: http://www.allfacebook.com/facebooks-sharespost-2011-12