According to real-time net worth tracking by Forbes, the 49-year-old Tesla and SpaceX executive has a fortune of $147.3 billion as of Tuesday afternoon. Meanwhile, Arnault's fortune sits at $182.4 billion. Both men remain below Amazon CEO Jeff Bezos, who reigns as the world's top billionaire at $188.5 billion.
The drop in Musk's net worth comes as Tesla stock is on pace for its fifth consecutive down week, the longest weekly losing streak since March 2018, and its worst month since March 2020.
Shares of Tesla, which closed up slightly at $577.87 at the end of Tuesday's trading session, are down 18.55% month-to-date and 18.11% year-to-date. The stock is also down 34.56% from its all-time closing high of $883.09 on Jan. 26, 2021.
Musk's recent comments have contributed to the volatility of cryptocurrency prices, including Bitcoin, Dogecoin and Ethereum.
Dogecoin plunged following Musk's hosting gig on "Saturday Night Live" earlier this month, after he called the joke currency "a hustle" during the NBC variety show's "Weekend Update" segment.
The meme token's co-creator, Jackson Palmer, slammed Musk as a "self-absorbed grifter" in a tweet last week, before deleting it just a minute later.
Musk's decision on May 12 that Tesla would no longer be accepting Bitcoin payments for its cars has also added fuel to the fire, causing similar price declines with Bitcoin and Ethereum.
"We are concerned about rapidly increasing use of fossil fuels for Bitcoin mining and transactions, especially coal, which has the worst emissions of any fuel," Musk said in a statement. "Cryptocurrency is a good idea on many levels and we believe it has a promising future, but this cannot come at great cost to the environment."
In addition to the reversal, Musk slammed Bitcoin for its "insane" energy consumption. According to Cambridge University's Bitcoin Electricity Consumption Index, the digital currency's energy usage has grown steadily since 2016.
However, Musk has assured investors that he remains a strong proponent of cryptocurrencies and clarified on Monday that the electric vehicle manufacturer has not sold any of the $1.5 billion in Bitcoin purchased earlier this year.
According to prices tracked by Coindesk, the world's largest cryptocurrency remains off its all-time high of more than $63,000, currently trading around $43,000 per coin as of the time of publication Tuesday. Ethereum is trading around $3,400 per coin and Dogecoin is trading at about 47 cents per coin.