ToplineElon Musk’s net worth has plummeted by more than $300 billion as SpaceX’s selloff extended into a third straight day on Monday, and the stock has wiped out all of its growth following a record-setting debut.A selloff for Musk’s rocket maker wiped out roughly $900 billion in market value. Getty ImagesKey FactsShares of SpaceX plunged more than 16% on Monday to under $155 as the stock fell below its debut close of $160.SpaceX’s stock has sunk more than 31% since hitting a peak of $225.64 on June 16, dropping Musk’s estimated net worth from an all-time high of $1.45 trillion to just over $1.1 trillion Monday.Monday’s drop alone wiped out more than $145 billion from Musk’s net worth, according to Forbes estimates.Musk holds a roughly 38% stake in SpaceX, including 4.8 billion shares and an additional 350 million stock options with an exercise price of $8.40 per share. A further decline followed MSCI—one of the world’s largest stock market index providers—reportedly awarding SpaceX a CCC rating, its lowest on a seven-tier sustainability scale, declaring the company was “lagging its industry” because of exposure to and management of “significant” environmental, social and governance risks. SpaceX also disclosed on Monday it would start issuing bonds to raise funds to refinance a short-term loan without diluting existing shareholders. big numberAbout $928 billion. That’s how much SpaceX’s market value has decreased since its June 16 peak of about $2.99 trillion, falling to around $2 trillion on Monday. The company briefly ranked ahead of Amazon and Microsoft as the fourth-largest company in the world by market capitalization, and SpaceX now ranks seventh, directly behind TSMC ($2.42 trillion).tangentSpaceX signed a computing agreement with AI startup Reflection AI that could be valued at $6.3 billion, CNBC reported Monday, citing materials of the deal. Reflection AI will pay SpaceX $150 million per month from July 1, 2026, through 2029, and have access to Nvidia GB300 chips to train and run advanced models. key backgroundSpaceX shares surged 67% above its $135 IPO price through a three-day streak, fueled by record-setting investor demand, though the broader market has cooled on the stock in recent days. The company announced last week it would acquire AI coding startup Cursor in an all-stock deal valued at $60 billion, diluting SpaceX’s $1.77 trillion IPO valuation by about 3.4%. Morningstar, which has remained bearish on SpaceX and claimed the stock was “overvalued,” criticized the acquisition as a “sizable dilution” of shares and lowered its fair value estimate to $62 a share, from $63. Other analysts have expressed concerns about the company’s governance structure, as Musk holds overwhelming voting power over shareholders, and some, including Swissquote analyst Ipek Ozkardeskaya, have claimed SpaceX could be the latest meme stock, arguing investors are buying the stock “in the expectation that others will buy too and push the price higher.”further readingForbesMusk’s Net Worth Hits $1.4 Trillion—SpaceX Passes Amazon As Fifth-Largest CompanyBy Ty RoushForbesSpaceX Stock Plunge Wipes Out $600 Billion After Cursor Deal Spooks InvestorsBy Ty Roush