Mark Zuckerberg, founder and chief executive of Facebook, and his wife Dr. Priscilla Chan celebrated the birth of their baby girl, and made the unexpected announcement that they plan to give away 99 percent of their shares in Facebook. The shares will be given out through an initiative that plans to “advance human potential and promote equality for all children in the next generation.”

USA Today reports that the shares, worth approximately $45 billion, will be given out over the course of their lifetime.  The announcement came in the form of a letter to the couple’s newborn daughter Max, posted to Facebook on Tuesday.

In the letter, Zuckerberg and Chan wrote, “Our initial areas of focus will be personalized learning, curing disease, connecting people, and building strong communities.”

The distribution of shares are not expected to affect Zuckerberg’s status as controlling shareholder any time soon. No more than $1 billion of Facebook stock will be given away each year, for the next three years. Zuckerberg will remain chairman and CEO of Facebook “for many, many years” according to a statement issued by the social media outlet.

The announcement was made by Zuckerberg and Chan at the close of trading, with Facebook shares showing hardly any changes in after-hours trading.

Zuckerberg and Chan have already donated over $1.6 billion dollars to philanthropic efforts from assisting struggling Bay Area communities, to funding the development of a new trauma center at San Francisco General Hospital, to funds used to help fight the spread of Ebola.

As announced last month, Zuckerberg plans to take two months of paternal leave, following the birth of his daughter. An interim leader has not been named by Zuckerberg or Facebook.