The world’s richest person could soon add another title to his name – America’s most leveraged CEO.

About two-thirds Elon MuskTakes over financing of the $44Billion deal TwitterPrivate funds will need to be taken out of the owner’s pocket. This is a deep pocket. His net worth is approximately $250 billion.

But because his wealth has been tied up TeslaMusk, in addition to equity in SpaceX, The Boring Co. and SpaceX, will need to sell millions of shares and promise millions to raise funds.

His SEC filings indicate that Musk’s financing planInclude $13 Billion in bank loans, $21 Billion in cash and likely from Tesla share sales. A $12.5 billion margin loan is also included, with Musk’s Tesla stock being collateral. According to documents, Musk must pledge Tesla stock worth $65 billion, which is about one quarter of his total current, to secure the loan.

Musk already had 88 million shares in the automaker for margin loans. However, it is not clear how much cash he has borrowed from this facility.

Audit Analytics reports that Musk holds more than $90 Billion in shares pledged to be loans. This makes Musk, in dollars terms, the biggest stock-debtor among directors and executives, surpassing Larry Ellison. OracleWith $24 Billion, he was the Chairman and Chief Technology Officer of the company, according to ISS Corporate Solutions. The Rockville-based provider ESG data, analytics, and information services, ISS Corporate Solutions.

Musk’s stock portfolio is larger than that of the whole stock market. Audit Analytics says that his shares of stock pledged to Musk before the Twitter deal amount to more than a quarter of $240 billion in pledged shares at all companies listed on NYSE and Nasdaq. This debt may rise even more with the Twitter borrowing.

Musk still has plenty of cash cushion due to the new stock options he receives as part of his 2018 pay plan. With 170million fully-owned Tesla shares combined with 73million options, Musk could have a stake of 23% in Tesla at an approximate value of more than $214 billion. Rest of his wealth comes from SpaceX’s more than half-owned stake and other ventures.

As Tesla continues to achieve its targets, he received 25 million more options in the Plan this Month. Musk cannot sell his options, but he is allowed to borrow against them for the next five years.

Musk’s eleven-figure share loan represents a completely new level of CEO leverage. Tesla’s share price fell by 12% this week, cutting Musk’s net worth to more than $20 Billion. Tesla shares were less than 1% lower on Thursday afternoon.

Musk’s wager also came as companies reduce or limit executive share borrowing. More than two-thirds of S&P 500 companies now have strict anti-pledging policies, prohibiting all executives and directors from pledging company shares for loans, according to data from ISS Corporate Solutions. While most companies do not have strict anti-pledging policies, some allow waivers or exceptions. Only 3% of companies in the S&P are similar to Tesla and allow share pledging by executives, according to ISS.

Following several scandalous incidents in which high-profile executives had to liquidate shares following margin calls from lenders, corporate concerns over excessive stock leverage stemmed from several cases. Green Mountain Coffee Roasters demoted Robert Stiller as chairman and William Davis as its chief director in 2012. The two were made to leave to satisfy margin demands. Valeant CEO Michael Pearson, who was responsible for the $100 million loan to him by Goldman Sachs in 2015 had to give up his shares.

Jun Frank, managing Director at ICS Advisory and ISS Corporate Solutions said that companies now are more conscious of the risk of executive pledging and feel greater pressure from investors for executive borrowing to be limited.

Frank stated that executives are considered to be a serious risk in corporate governance by pledging shares. If an executive who has pledged substantial ownership could fail to meet the margin call it could result in sales which may cause a steep drop in share price.

Tesla claims that the key to its compensation structure is allowing directors and executive to borrow against their shares in its SEC filings.

Tesla stated in filings that the ability for our executives and directors to pledge Tesla stock to personal loans or investments was inherently linked to their compensation through our equity awards and promotion long-termism. These individuals have the ability to plan for their finances without being dependent on selling shares, which aligns with our stockholders’ interests.

Musk’s exact borrowing amount against shares is still unknown. Tesla’s SEC filings reveal that he pledged 88 million shares but do not show how much money he has actually borrowed. He could have borrowed about $2 billion if he had pledged shares at Tesla’s $90 price in 2020. He could borrow $20 billion more to cover the remaining 88 million shares pledged. Today the borrowing power for those shares is ten times greater. Only about a third would remain in Tesla after the Twitter deal.

He may be required to pledge additional shares, however, if he has increased his borrowing due to Tesla shares rising in value. If Musk is unable to repay the full 88 million share of his debt and has to pledge 60 million more shares in order to finance the Twitter deal, then Musk could be required to pledge additional shares.

This would leave him with approximately $25 billion of Tesla shares that are not pledged. To pay for the $21billion cash and capital gains tax, he would also have to sell Tesla shares totaling $25 billion.

Musk is putting his Tesla wealth at stake in either case, and it could mean a rough ride ahead for Tesla shareholders.

Frank explained that borrowing against shares exposes shareholders to stock price risks due to executive financing decisions.