Mark Zuckerberg sells another $95 Million in Facebook stock

He is keeping his pledge to give away 99% of his shares to make the world a 'better place'

Facebook CEO Mark Zuckerberg has sold another $95 million from his company's stock, keeping his pledge to give away 99 per cent of his shares to make the world a "better place".

The Chan Zuckerberg Foundation and CZI Holdings LLC, the two entities that Zuckerberg and his wife Priscilla Chan created for their philanthropy and public advocacy last year, sold the shares between November 17 and November 18, according to regulatory filings, quoted by Forbes.

The sale follows $190 million in Facebook stock sold by the same entities in October and another $190 million sold in September.

Zuckerberg, 32, says he will not sell or give away more than $1 billion in Facebook stock per year through 2018, the filing reported.

In December 2015, Zuckerburg and Chan had first announced to give away 99 per cent of their company's stake, which was then worth about $45 billion, in a letter to their baby to make the world a "better place", for "philanthropic, public advocacy and other activities for the public good" over their lifetime.

Some of the funds will go into for profit companies that fit with the couple's goals. Following these sales, Forbes estimates Zuckerberg's net worth at $52 billion. His net worth has increased over the past year despite the stock sales as a result of the rise in Facebook's stock price.

Chan and Zuckerberg announced one big goal in September, when they pledged to spend $3 billion over the next decade to fight disease.

"If we can develop new tools, we can empower scientists all around the world to make much faster progress and breakthroughs," Zuckerberg had said.

Zuckerberg is currently the fourth richest person in the world, according to Forbes estimates.