Elon Musk on Monday became the first person ever worth $600 billion, Forbes said, on the heels of reports that his SpaceX startup was likely to go public at a valuation of $800 billion.

Axar.az informs, citing Reuters, Musk, who was the first to surpass $500 billion in net worth in October, owns an estimated 42 percent stake in SpaceX, which is preparing to go public next year, Reuters reported last week.

The SpaceX valuation would strengthen Musk’s wealth by $168 billion to an estimated $677 billion as of 12 p.m. ET on Monday, according to Forbes.

Musk’s wealth also got a boost from his roughly 12 percent stake in EV maker Tesla, shares of which have risen 13 percent so far this year, despite flagging sales. They were up nearly 4 percent on Monday after Musk said the company was testing robotaxis without safety monitors in the front passenger seat.

In November, Tesla shareholders approved a $1 trillion pay plan for Musk, the largest corporate pay package in history, as investors endorsed his vision of morphing the EV maker into an AI and robotics juggernaut.

As well, his artificial-intelligence startup xAI is in advanced talks to raise $15 billion in fresh equity at a valuation of $230 billion, according to a media report.