And while many new dads are preoccupied with figuring out how to make ends meet, Zuckerberg clearly doesn't have this problem.

To celebrate the new arrival of their new daughter, Max, he and his wife Priscilla Chan, have decided to give away most of their fortune over the course of the rest of their lives.

They said they are doing this to "further the mission of advancing human potential" and to promote "equality by means of philanthropic, public advocacy, and other activities for the public good".

Writing to their newborn daughter, Max, in a post published on Facebook, the new parents said they would transfer 99 per cent of their shares in the social network to the "Chan Zuckerberg Initiative, a new vehicle they have established that would initially be focused on promoting "personalised learning, curing disease, connecting people and building strong communities".

A Facebook spokesperson confirmed to Fairfax Media that The Chan Zuckerberg Initative will be structured as a limited liability company rather than a nonprofit or foundation. The New York Times noted that under US laws, this would allow it "to go beyond making philanthropic grants" and do things like invest in companies, lobby for legislation and influence policy debates.

"Like all parents, we want you to grow up in a world better than ours today," they wrote in the letter. "But right now, we don't always collectively direct our resources at the biggest opportunities and problems your generation will face."

"Consider disease. Today we spend about 50 times more as a society treating people who are sick than we invest in research so you won't get sick in the first place."

Priscilla and I are so happy to welcome our daughter Max into this world!For her birth, we wrote a letter to her about...Posted by Mark Zuckerberg on  Tuesday, December 1, 2015

The financial details of Zuckerberg's charitable push followed in a filing to the US stock market regulator.

Zuckerberg, who's the world's eighth-richest man, owns about 4 million shares of Facebook common stock (worth about $US428 million) and about 419 million shares of its super-voting stock (worth about $US44 billion).

The company employs a dual class share structure, that has enabled Zuckerberg to retain control following the company's IPO in 2012. (Rupert Murdoch's News Corp employs a similar structure, and so will Australia's Atlassian after its planned IPO).

The filing said Zuckerberg would sell or gift no more than $US1 billion of Facebook stock each year for the next three years ,and that he intends to retain his majority voting position in the company for the foreseeable future.

Bill Gates, the former Microsoft CEO and still the world's richest man with an estimated wealth of $84.6 billion, pledged to give away most of his fortune to charity when he stepped down from the company behind the Windows operating system in 2008.

Warren Buffett, the legendary billionaire US investor and the world's third-richest man, has also pledged to give much of his fortune away.

Zuckerberg and his wife joined Bill Gates' and Warren Buffett's billionaires' The Giving Pledge movement and have already pledged $1.6 billion to philanthophy, a spokesperson said

But the Facebook billionaire's announcement today seems to take corporate philanthropy to a new level, given he's only 31 years old.

"We will give 99 per cent of our Facebook shares - currently about $US45 billion - during our lives to advance this mission," they said.

Zuckerberg has been an active supporter of charity in the past, but his desire to spread the internet to poor, unconnected regions in emerging markets through his nonprofit Internet.org, has previously been criticised for benefiting Facebook.