Social networking has become a huge part of American life in the past decade or so. Starting Monday, Facebook, one of the most popular social networking websites will become a part of Standard & Poor’s 500-stock index.

At the close of trading on Friday, December 20, 2013, Facebook will be a part of that index.

That’s right, Mark Zuckerberg is selling more shares for Facebook. According to The NY Times, the social networking site is offering 70 million more shares to the public on Monday. This is the second offering since Facebook went public last year.

Those who missed out on the selling of shares in May 2012, will have a chance to buy stock in Facebook at the current price of $55.50. According to Forbes, the shares Zuckerberg is selling are worth $2.3 billion.

Though Zuckerberg will be selling millions of shares, it will only slightly loosen his control on the company. His voting rights will still be 60 percent.

The filing also said that Zuzkerberg intends on making a charitable gift of approximately 18 million shares, or $1 billion, this month. He plans to donate these shares to the Silicon Valley Community Foundation, a charity on which he has donated before.

The young company has come very far since 2004 and has the potential to make billions of dollars at the end of the trade day Monday.