As Facebook prepares to go public on Friday, many news articles, such as this Forbes article, have discussed the fact that Facebook co-founders Mark Zuckerberg and Dustin Moskovitz have funded annuity trusts, most likely Grantor Retained Annuity Trusts (GRATs), with Facebook stock.  This stock is set to increase exponentially in value with the IPO takes place on May 18.  If these annuity trusts are, in fact, GRATs, they may be transferring millions of dollars worth of Facebook stock to their beneficiaries, potentially free of any transfer tax.