MASHABLE - Dec 2 - November was a good month for Facebook and its CEO Mark Zuckerberg. Facebook‘s stock shot up from $21.08 a share on the first day of trading in November to $28 a share at the end of the day Friday, its highest price since July. Zuckerberg, who owns ~504M shares of Facebook stock, gained ~$3.48 billion as a result. As of Friday, Zuckerberg’s net worth was $14.1 billion and will likely only continue to grow in December.